Chapter02 Data Types Control Structures

8/8/2019 Chapter02 Data Types Control Structures

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2004 Trn Minh Chu. FOTECH. VNU Chng 2.

1

Ngn ng lp trnh C++Chng 2 Cc kiu d liu c bn

Cc cu trc iu khin


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2

Ti liu c thm

Ti liu c thm cho chng ny: Section 2.1. Complete C++ Language Tutorial (CCLT)

Day 7. Teach Yourself C++ in 21 Days (TY21)

Namespace (Sec.5-2.CCLT) (Khng bt buc)


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3

Chng 2 Kiu d liu v php ton c bnCu trc iu khin v cu trc chng trnh

mc

2.1 Cc kiu d liu c bn

2.2 Cc php gn tt, php tng, php gim

2.3 Cc php ton logic

2.4 Thut ton, m gi, iu khin ca chng trnh, s khi

2.5 S lc v cc cu trc iu khin

2.6 Cu trc la chn if, if/else

2.7 Php ton la chn 3 ngi2.8 Cu trc lpwhile

2.9 Thit lp thut ton

2.10 iu khin lp bng con m v gi tr canh


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4

mc (tip theo)

2.11 Cc cu trc lng nhau

2.12 Vng lp for

2.13 Cu trc a la chn switch

2.14 Vng lp do/while

2.15 break v continue

2.16 S lc v lp trnh cu trc

Chng 2 Kiu d liu v php ton c bnCu trc iu khin v cu trc chng trnh


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5

2.1 Cc kiu d liu c bn

char k t hoc s nguyn 8 bitshort s nguyn 16 bit

long s nguyn 32 bit

int s nguyn di bng 1 word (16 bithoc 32 bit)

float s chm ng 4 byte

double s chm ng 8 byte

long double s chm ng 10 byte

bool gi tr Boolean, true hoc false

wchar_t k t 2 byte, lu bng ch ci quc t


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6

2.2 Cc php ton c bn

php gn assignation (=)x = 5; //x: lvalue, 5: rvalue

l biu thc c gi tr l gi tr c gn

cc php ton s hc - Arithmetic operators(+, -, *, /, %)

cc php gn kp - Compound assignationoperators

(+=, -=, *=, /=, %=, >>=,


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7

2.2 Cc php ton c bn

cc php quan h - relational operators( ==, !=, >, =,


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8

2.2 Cc php gn tt

Cc biu thc gn tt - Assignment expressionabbreviations Php gn cng

c = c + 3; vit tt thnh c += 3;

Cc lnh c dngvariable = variableoperatorexpression;c th c vit li thnh

variableoperator= expression;

Cc php gn khcd -= 4 (d = d - 4)e *= 5 (e = e * 5)

f/= 3 (f = f/ 3)

g %= 9 (g = g % 9)


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9

2.2 Cc php tng v gim

Php tng - Increment operator (++) c th c dng thay cho c += 1

Php gim - Decrement operator (--) c th c dng thay cho c -= 1

Tng/gim trc Preincrement/Predecrement ++c hoc --c

Gi tr ca bin b thay i, sau biu thc cha n c tnh gi tr.

Biu thc c gi tr l gi tr ca bin sau khi tng/gim

Tng/gim sau - Postincrement/Predecrement c++ hoc c--

Biu thc cha bin c thc hin, sau bin c thay i.

Biu thc c gi tr l gi tr ca bin trc khi tng/gim


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10

2.2 Cc php tng v gim

V d: nu c = 5 cout


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2004 Trn Minh Chu.FOTECH. VNU.

11

fig02_14.cpp

(1 of2)

1 // Fig. 2.14: fig02_14.cpp

2 // Preincrementing andpostincrementing.

3 #include

4

5 using std::cout;

6 using std::endl;7

8 //functionmainbeginsprogramexecution

9 int main()

10 {

11 int c; //declare variable

12

13 //demonstratepostincrement14 c = 5; //assign 5 toc

15 cout


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12


c dng lm iu kin trong cc vng lp vlnh if

&& (logical AND) true nu c hai iu kin l true

if ( gender == 1 &&age>= 65 )

++seniorFemales;

|| (logical OR) true nu t nht mt trong hai iu kin l true

if ( semesterAverage>= 90 ||finalExam>= 90 )cout


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13


! (logical NOT, ph nh logic logical negation) tr v gi tr true khi iu kin l false, v ngc li

if ( !( grade == sentinelValue ) )cout


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14

Nhm ln giaphp so snh bng (==) v php gn (=)

Li thng gp Thng khng to li c php (syntax error)

Cc kha cnh ca vn biu thc c gi tr c th c dng lm iu kin

bng khng = false, khc khng = true

Cc lnh gn cng to gi tr (gi tr c gn)


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15


V dif ( 4 == payCode )

cout


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16


Lvalue l biu thc c th xut hin ti v tri ca php gn

xc nh mt vng nh c th c gn tr (i.e, cc bin) x = 4;

Rvalue ch xut hin bn phi php gn

hng, cc gi tr (literal) khng th vit 4 = x;

Lvalue c th c dng nh cc rvalue, nhngchiu ngc li l khng th


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17

Vit chng trnh

Trc khi vit chng trnh Hiu k bi ton

Lp k hoch gii quyt bi ton

Trong khi vit chng trnh Bit li gii c sn cho cc bi ton con S dng cc nguyn l lp trnh tt


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18

Thut ton - Algorithm

Cc bi ton tin hc c gii bng cch thc hin mt chui hnh ng theo

mt th t c th

Thut ton: mt quy trnh quyt nh

Cc hnh ng cn thc hin Th t thc hin

V d: cch nu mt mn n

iu khin ca chng trnh Program Control Ch ra th t thc hin cc lnh


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19

M gi - Pseudocode

M gi: ngn ng khng chnh thc c dng m t thut ton tng t vi ngn ng hng ngy

Khng chy c trn my tnh dng m t chng trnh trc khi vit chng trnh

d chuyn thnh chng trnh C++

ch gm cc lnh chy khng cn khai bo bin

V d:tm s nh hn trong hai s

1. nhp 2 s x,y

2. nu x>y th in y ra mn hnh

3. nu khng, in x ra mn hnh


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20

Cc cu trc iu khin - Control StructuresKhi nim

Thc thi tun t - Sequential execution Cc lnh c thc hin theo th t tun t

Chuyn iu khin - Transfer of control Lnh tip theo c thc thi khng phi lnh tip theo trong

chui lnh.

3 cu trc iu khin Cu trc tun t - Sequence structure

theo mc nh, chng trnh chy tun t tng lnh

Cc cu trc chn la - Selection structures if, if/else, switch

Cc cu trc lp - Repetition structures while, do/while, for


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21

Cc cu trc iu khin

Cc t kha ca C++ Khng th dng lm tn bin hoc tn hm

C++ Keywords

Keywords common to theC andC++ programminglanguages

auto break case char const

continue default do double else

enum extern float for goto

if int long register return

short signed sizeof static struct

switch typedef union unsigned void

volatile while

C++ only keywordsasm bool catch class const_cast

delete dynamic_cast explicit false friend

inline mutable namespacenew operator

private protected public reinterpret_cast

static_cast template this throw true

try typeid typename using virtual

wchar_t


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22

Cc cu trc iu khin

S khi - Flowchart

m t thut ton bng hnh v gm cc k hiu c bit c ni bng cc mi tn(flowlines)

Hnh ch nht (k hiu hnh ng) kiu hnh ng bt k

k hiu oval

Bt u hoc kt thc mt chng trnh,hoc mt on m (hnh trn)

Cc cu trc iu khin c ng 1 u vo, 1 u ra Kt ni u ra ca mt cu trc iu khin vi u vo ca

cu trc tip theo xp chng cc cu trc iu khin

true

false

grade >= 60 print Passed


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23

Cu trc la chn if

Cu trc la chn - Selection structure chn gia cc tuyn hnh ng khc nhau

v d bng m gi:Ifstudents grade is greaterthan orequal to 60

Print Passed Nu iu kin tha mn (c gi tr true)

lnh Print c thc hin, chng trnh chy tip lnh tip theo

Nu iu kin khng tha mn (c gi tr false)

lnh Print b b qua, chng trnh chy tip

Cch vit tht u dng lm chng trnh d c hn C++ b qua cc k t trng (tab, space, etc.)


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24

Cu trc la chn if

Dch sang C++Ifstudents grade is greaterthan orequal to 60

Print Passed

if ( grade>= 60 )

cout = 60 print Passed

Mt biu thc bt k uc th c s dng lmiu kin cho la chn.

bng 0- false

khc 0- true

V d:

3 - 4 c gi tr true


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25

Cu trc chn la if/else

if Thc hin hnh ng nu iu kin tha mn

if/else

thc hin nhng hnh ng khc nhau ty theo iu kin ctha mn hay khng

m giifstudents grade is greaterthan orequal to 60

print Passed

else

print Failed

m C++if ( grade>= 60 )

cout


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26


php ton iu kin 3 ngi (?:) ba tham s (iu kin, gi tr nu true, gi tr nu false)

m c th c vit:cout = 60 ? Passed : Failed );

truefalse

print Failed print Passed

grade >= 60

Condition Value if true Value if false


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27


Cc cu trc if/else lng nhau lnh ny nm trong lnh kia, kim tra nhiu trng hp

Mt khi iu kin tha mn, cc lnh khc b b quaifstudents grade is greaterthan orequal to 90

Print A

elseifstudents grade is greaterthan orequal to 80Print B

elseifstudents grade is greaterthan orequal to 70Print C

elseifstudents grade is greaterthan orequal to 60Print D

else

Print F


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28


V dif ( grade>= 90 ) // 90 andabove

cout = 80 ) // 80-89

cout = 70 ) // 70-79

cout = 60 ) //60-69

cout


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29


lnh phc compound statement tp lnh bn trong mt cp ngoc

if ( grade>= 60 )cout


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30

Cu trc lp while

Cu trc lp - Repetition structure hnh ng c lp i lp li trong khi mt iu kin no

cn c tha mn

m giT

rong khi vn cn tn hng trongdanhsch i ch ca tiMua mt hng tip theo v gch tn n ra khi danhsch

vngwhile lp i lp li cho n khi iu kin khng thamn


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31

Cu trc lp while

V dintproduct = 2;

while ( product


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32

Thit lp thut ton(iu khin lp bng con m)

Vng lp c iu khin bng con m (counter) Lp n khi con m t n gi tr no

Lp hu hn - Definite repetition s ln lp bit trc

V dMt lp gm 10sinh vin lmmt bi thi. Cho bit cc imthi (snguyn trong khong t 0 n 100). Tnh trung bnhim thi ca lp.


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33

Thit lp thut ton(iu khin lp bng con m)

M gi cho v d:t tng bng 0

t con m bng 1

Trong khi con m nh hn hoc bng 10Nhp im tip theoCng im vo tngThm 1 vo con n

t trung bnh lp bng tng chia cho 10

In trung bnh lp

Tip theo: M C++ cho v d trn


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34

fig02_07.cpp

(1 of2)

1 // Fig. 2.7: fig02_07.cpp

2 //Classaverageprogramwithcounter-controlledrepetition.

3 #include

4

5 using std::cout;

6 using std::cin;

7 using std::endl;

8


10 int main()

11 {

12 int total; //sumof gradesinputbyuser13 int gradeCounter; //numberof gradetobeenterednext

14 int grade; // grade value

15 int average; //averageof grades

16

17 //initializationphase

18 total = 0; //initializetotal

19 gradeCounter = 1; //initializeloopcounter20


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35

fig02_07.cpp

(2 of2)

fig02_07.cpp

output (1 of1)

21 //processing phase

22 while ( gradeCounter grade; //read gradefromuser

25 total = total + grade; //add gradetototal

26 gradeCounter = gradeCounter + 1; //incrementcounter

27 }

28

29 //terminationphase

30 average = total/10; //integerdivision

31

32 //displayresult33 cout


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36

Thit lp thut ton(iu khin lp bng lnh canh)

Gi s bi ton tr thnh:Vitmt chng trnh tnh im trung bnh ca lp, chngtrnhsx l mtslng im ty mi khi chy chngtrnh.

S sinh vin cha bit Chng trnh s lm th no bit khi no th kt thc?

Gi tr canh K hiu Kt thc ca d liu vo

Vng lp kt thc khi nhp canh Canh c chn khng b ln vi d liu vo thngthng

trong trng hp ny l -1


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37


Thit k t trn xung, lm mn tng bc Bt u bng m gi cho mc cao nht

Tnh trung bnh im thi ca lp

Chia thnh cc nhim v nh hn, lit k theo th t

Khi to cc binNhp, tnh tng, v m cc im thi

Tnh v in trung bnh im thi


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38


Nhiu chng trnh c 3 pha Khi to - Initialization

Khi to cc bin chng trnh

X l - Processing

Nhp d liu, iu chnh cc bin trong chng trnh Kt thc - Termination

Tnh v in kt qu cui cng

Gip vic chia nh chng trnh lm mn t trn xung


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39


Lm mn pha khi toKhi to cc bin

thnh

Khi to tng bng 0

Khi to bin m bng 0

X lNhp, tnh tng, v m cc im thi

thnh

Nhp im u tin (c th l canh)

Trong khi ngi dng cn cha nhp canh

Cng im va nhp vo tng

Cng thm 1 vo bin m im

Nhp im tip theo (c th l canh)


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40


Kt thcTnh v in trung bnh im thi

thnh

Nu con m khc 0

t trung bnh bng tng chia cho con m

In gi tr trung bnh

Nu khng

In Khng nhp im no

Tip theo: chng trnh C++


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41

fig02_09.cpp

(1 of3)

1 // Fig. 2.9: fig02_09.cpp

2 //Classaverageprogramwithsentinel-controlledrepetition.

3 #include

4

5 using std::cout;

6 using std::cin;

7 using std::endl;

8 using std::fixed;

9

10 #include //parameterizedstreammanipulators

11

12 using std::setprecision; //setsnumericoutputprecision13


15 int main()

16 {

17 int total; //sumof grades

18 int gradeCounter; //numberof gradesentered

19 int grade; // grade value20

21 double average; //numberwithdecimalpointforaverage

22

23 //initializationphase

24 total = 0; //initializetotal

25gradeCounter

= 0;//

initialize

loop

counter

D liu kiu double dng biu din s thp phn.


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42

fig02_09.cpp

(2 of3)

26

27 //processing phase

28 // getfirst gradefromuser

29 cout > grade; //read gradefromuser

3132 //loopuntilsentinel valuereadfromuser

33 while ( grade!= -1 ) {

34 total = total + grade; //add gradetototal

35 gradeCounter = gradeCounter + 1; //incrementcounter

36

37 cout > grade; //readnext grade

39

40 }//endwhile

41

42 //terminationphase

43 //ifuserenteredatleastone grade ...

44 if ( gradeCounter!= 0 ) {45

46 //calculateaverageofall gradesentered

47 average = static_cast< double >( total ) / gradeCounter;

48

static_cast() coi total nh mt double tm thi (casting).

Cn thit v php chia s nguyn b qua phn d.gradeCounter l mt bin int, nhng n c nng ln kiu double.

43


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43

fig02_09.cpp

(3 of3)

fig02_09.cpp

output (1 of1)

49 //displayaveragewithtwodigitsofprecision

50 cout


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44

Cc cu trc iu khin lng nhau

Pht biu bi tonMt trng c danhsch ktqu thi (1 = , 2 = trt) ca10sinh vin. Vitmt chng trnh phn tch ktqu thi.

Nu c nhiu hn 8sinh vin th in ra mn hnh dngch Tng tin hc ph".

Lu Chng trnh x l 10 kt qu thi

s ln lp c nh, s dng vng lp iu khin bng bin m

C th s dng hai con m Mt con m m s lng

Mt con m khc m s lng trt

Mi kt qu thi ch l 1 hoc 2 Nu khng phi 1 th coi l 2

45


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45


Phc tho mc cao nht - Top level outlineAnalyzeexamresults anddecide iftuitionshouldberaised

Lm mn ln mt - First refinementInitialize variables

Input the ten quiz grades andcount passes andfailuresPrint asummaryoftheexamresults anddecide iftuitionshouldberaised

Lm mn - RefineInitialize variables

to

Initialize passes tozero

Initializefailures tozero

Initializestudent countertoone

46


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46


RefineInput the ten quiz grades andcount passes andfailures

to

Whilestudent counteris less than orequal to tenInput the nextexamresult

Ifthestudent passed

Addone to passesElse

Addone tofailures

Addone tostudent counter

47


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47


tip tc lm mnPrint asummaryoftheexamresults anddecide iftuitionshould

beraised

to

Print the numberofpasses

Print the numberoffailuresIfmore than eightstudents passed

Print Raise tuition

Program next

48


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48

fig02_11.cpp

(1 of2)

1 // Fig. 2.11: fig02_11.cpp

2 //Analysisofexaminationresults.

3 #include

4

5 using std::cout;

6 using std::cin;

7 using std::endl;

8


10 int main()

11 {

12 //initialize variablesindeclarations13 int passes = 0; //numberofpasses

14 int failures = 0; //numberoffailures

15 int studentCounter = 1; //studentcounter

16 int result; //oneexamresult

17

18 //process 10 studentsusing counter-controlledloop

19 while ( studentCounter result;

24

49


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49

fig02_11.cpp

(2 of2)

25 //ifresult 1,incrementpasses; if/elsenestedinwhile

26 if ( result == 1 ) //if/elsenestedinwhile

27 passes = passes + 1;

28

29 else //ifresultnot 1,incrementfailures

30 failures = failures + 1;31

32 //incrementstudentCountersoloopeventuallyterminates

33 studentCounter = studentCounter + 1;

34

35 }//endwhile

3637 //terminationphase; displaynumberofpassesandfailures

38 cout


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50

fig02_11.cpp

output (1 of1)

Enterresult (1 = pass, 2 = fail): 1










Passed6

Failed

4






Enterresult (1 = pass, 2 = fail): 1Enterresult (1 = pass, 2 = fail): 1




Passed 9

Failed 1

Raisetuition

51


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51

Nhng im quan trng vvng lp iu khin bng con m

vng lp iu khin bng con m i hi Tn ca bin iu khin(control variable) hay bin m

(loop counter)

Gi tr khi to ca bin iu khin

iu kin kim tra gi tr cui cng Tng/gim bin m khi thc hin vng lp

int counter = 1; // initialization

while ( counter


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52

fig02_16.cpp

(1 of1)

1 // Fig. 2.16: fig02_16.cpp

2 //Counter-controlledrepetition.

3 #include

4

5 using std::cout;

6 using std::endl;7


9 int main()

10 {

11 int counter = 1; //initialization

1213 while ( counter


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53

Cu trc vng lp for

Dng tng qut ca vng for

for ( khi_to; iu_kin_lp; tng/gim )

lnh

V dfor( intcounter = 1; counter


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54

fig02_17.cpp

(1 of1)

1 // Fig. 2.17: fig02_17.cpp

2 //Counter-controlledrepetitionwiththeforstructure.

3 #include

4

5 using std::cout;

6 using std::endl;7


9 int main()

10 {

11 // Initialization,repetitionconditionandincrementing

12 //are

all

included

in

the

for

structure

header

.13

14 for ( int counter = 1; counter


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55

Cu trc vng lp for

vng for thng c th vit c thnh vngwhile tng ng

khi_to;

while ( iu_kin_lp){

lnh

tng/gimbin m;}

Khi to v tng bin m

nu s dng nhiu bin m, s dng du phy tchfor (inti = 0, j = 0; j + i


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fig02_20.cpp

(1 of1)

fig02_20.cpp

output (1 of1)

1 // Fig. 2.20: fig02_20.cpp

2 // Summationwithfor.

3 #include

4

5 using std::cout;

6 using std::endl;7


9 int main()

10 {

11 int sum = 0; //initializesum

12

13 //sumevenintegersfrom 2 through 100

14 for ( int number = 2; number


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V d s dng vng for

Chng trnh tnh li kp (compound interest) Mt ngi u t $1000.00 vo mt ti khon tit kim vi li sut

5%. Gi s tin li c gp vi vn trong ti khong, tnh v in ra stin t rong ti khon vo cui mi nm trong vng 10 nm. Sdngcng thc sau t nh cc khon tin :

a = p(1+r)

p : khon u t ban u (i.e., the principal),r: li sut hng nm, (interest rate)

n : s nm, va : lng tin c trong ti khon (amount on deposit)vo cui nm th n

n

581 // Fi 2 21 fi 02 21


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fig02_21.cpp

(1 of2)

1 // Fig. 2.21: fig02_21.cpp

2 //Calculating compoundinterest.

3 #include

4

5 using std::cout;

6 using std::endl;7 using std::ios;

8 using std::fixed;

9

10 #include

11

12 usingstd

::setw

;13 using std::setprecision;

14

15 #include //enablesprogramtousefunctionpow

16


18 int main()

19 {20 double amount; //amountondeposit

21 double principal = 1000.0; //starting principal

22 double rate = .05; //interestrate

23

header cn chohmpow (chng trnh skhng dch nu khng c khai

bo ny).


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60Year Amount on deposit


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fig02_21.cpp

output (1 of1)

Year Amountondeposit

1 1050.00

2 1102.50

3 1157.63

4 1215.51

5 1276.28

6 1340.10

7 1407.10

8 1477.46

9 1551.33

10 1628.89

Cc s c cn phi do cc lnh

setw (vi tham s c gi tr 4 v 21).

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Cu trc a la chn switch

switch

Test bin vi nhiu gi tr chui cc nhn case trng hp default khng bt buc

switch ( variable ) {

case value1: //takenif variable == value1statements

break; //necessarytoexitswitch

case value2:

case value3: //takenif variable == value2 or == value3

statementsbreak;

default: //takenif variablematchesnoothercases

statementsbreak;

}

62


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true

false

.

.

.

case a case a action(s) break

case b case b action(s) break

false

falsecase z

case z action(s) break

true

true

default action(s)

63


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V d sp ti Chng trnh c xp loi im (A-F) Hin s lng mi xp loi c nhp

Chi tit v cc k t Cc k t n thng c lu bng kiu d liu char

char: s nguyn 1-byte, c th c lu di dng cc gi tr int C th coi k t l int hoc char

97 l biu din dng s ca ch a thng (ASCII) dng cp nhy n ly biu din ch ca k t

cout


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fig02_22.cpp

(1 of4)

1 // Fig. 2.22: fig02_22.cpp

2 //Counting letter grades.

3 #include

4

5 using std::cout;

6 using std::cin;7 using std::endl;

8


10 int main()

11 {

12 int grade; //one grade

13 int aCount = 0; //numberofAs

14 int bCount = 0; //numberof Bs

15 int cCount = 0; //numberofCs

16 int dCount = 0; //numberofDs

17 int fCount = 0; //numberof Fs

18

19 cout


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66

43 case 'D': // grade was uppercase D


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fig02_22.cpp

(3 of4)

43 case D : // gradewasuppercaseD

44 case 'd': //orlowercased

45 ++dCount; //incrementdCount

46 break; //exitswitch

47

48 case 'F': // gradewasuppercase F49 case 'f': //orlowercasef

50 ++fCount; //incrementfCount


52

53 case '\n': //ignorenewlines,

54 case '\t': //tabs,

55 case ' ': //andspacesininput


57

58 default: //catchallothercharacters

59 cout


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fig02_22.cpp

(4 of4)

67 //outputsummaryofresults

68 cout


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fig02_22.cpp

output (1 of1)

Entertheletter grades.

EntertheEOF charactertoendinput.

a

B

c

CA

d

f

C

E

Incorrectletter gradeentered. Enteranew grade.

D

A

b

^Z

Totalsforeachletter gradeare:A: 3

B: 2

C: 3

D: 2

F: 1

69


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Cu trc lp do/while

Tng t cu trcwhile Kim tra iu kin tip tc lp

cui, khng kim tra u

Thn vng lp chy t nht mtln

Cng thcdo {

statements

}while ( condition );

true

false

action(s)

condition


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71


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Cc lnh break v continue

break Thot ngay ra khi cc cu trc while, for, do/while,

switch

Chng trnh tip tc chy ti lnh u tin ngay sau cutrc

thng c s dng Thot khi vng lp sm hn bnh thng b qua phn cn li ca switch

721 // Fig. 2.26: fig02_26.cpp


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2004 Trn Minh Chu.

FOTECH. VNU.

fig02_26.cpp

(1 of2)

2 // Using thebreakstatementinaforstructure.

3 #include

4

5 using std::cout;

6 using std::endl;


9 int main()

10 {

11

12 int x; //xdeclaredheresoitcanbeusedaftertheloop

13

14 //loop 10 times

15 for ( x = 1; x


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Cc lnh break v continue

continue c dng trong while, for, do/while

b qua phn cn li ca thn vng lp

chy tip ln lp tip theo

vi cc vngwhile v do/while thc hin kim tra iu kin lp ngay sau lnh continue

vi vng for biu thc tng/gim bin m c thc hin

sau , iu kin lp c kim tra

74

1 // Fig. 2.27: fig02_27.cpp


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2004 Trn Minh Chu.

FOTECH. VNU.

fig02_27.cpp

(1 of2)

2 // Using thecontinuestatementinaforstructure.

3 #include

4

5 using std::cout;

6 usingstd

::endl

;7


9 int main()

10 {

11 //loop 10 times

12 for ( int x = 1; x


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Lp trnh cu trcStructured-Programming

Lp trnh cu trc Structured programming Chng trnh d hiu, test, tm li (debug) v d sa i hn Cc quy tc lp trnh cu trc

Ch s dng cc cu trc iu khin mt u vo mt u ra

Quy tc1) Bt u bng mt s khi n gin nht

2) Mi hnh ch nht (hnh ng) c th c thay bng mtchui gm 2 hnh ch nht khc

3) Mi hnh ch nht (hnh ng) c th c thay bng mt cu

trc iu khin ty (tun t, if, if/else, switch, while,do/while hoc for)

4) Cc quy tc 2 v 3 c th c p dng nhiu ln v theo tht ty

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Lp trnh cu trc


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Lp trnh cu trcStructured-Programming

Qui tc 3

Qui tc 3Qui tc 3

M t quy tc 3 (thay mt hnh ch nht ty bng mt cu trc iu khin)

Documents

Chapter02 Data Types Control Structures