a) Chng minh rng mt chng trnh c th hin bng tt c cc cu trc lnh (while, do..while, for, if..else, switch) u c th chuyn i thnh mt chng trnh mi cho li kt qu ging nh chng trnh c nhng ch cn dng ti thiu cu trc lnh lp while v mt s bin ph. b) p dng kt qu trn chuyn i cc bi 1 trong cc bi tp n s dng ti thiu cu trc lnh lp while v mt s bin ph. 1. Chuyn i t cu trc A sang cu trc B: Thut ton chuyn i: Duyt t u n cui vn bn chng trnh: 1. Nu gp cu trc lnh while: ta gi nguyn khng phi lm g. 2. Nu gp cu trc lnh for ta chuyn i tng ng vi while theo nguyn tc bt1; For (bt1 ; bt2 ; bt3){ while(bt2){ ; ; } Bt3; } 3. Nu gp cu trc lnh do..while ta chuyn i tng ng vi while theo nguyn tc: Do { ; }while(Bt); ; while(bt){ ; }

4. Nu gp cu trc lnh switch() chuyn i thnh if..else theo nguyn tc: Switch(bt){ Case H1: ; Break; Case H2: ; Break; ... . Case Hn: ; Break; Default: ; Break; } If (bt ==H1) ; Else if (bt==H2) ; ...... Else if (bt ==Hn) Else ;

5. Sau khi thc hin bc 1, 2, 3, 4 ta ch cn li if..else cha c chuyn tng ng vi while. Chuyn i if..else tng ng vi while bng cch thm vo bin ph theo nguyn tc: If (bt ) { ;} Else { ; } int OK=0;//bin ph cn thm while(bt) { ; OK=1; Break; } While (!OK) { ; Break; }