Greatest common divisor and least common multiple algorithm implementation

Greatest common divisor

1. Using the most basic method of loop traversal

2. Using the divide-and-toss method

3. Subtraction with the use of the tossing phase

See also:http://baike.baidu.com/view/47637.htm

1#include <iostream>2 using namespacestd;3 4 intCommondivisor (intXinty);5 intCommonmultiple (intXinty);6 intCommonDivisor1 (intXinty);7 intCommonMultiple2 (intXinty);8 intCommonDivisor2 (intXinty);9 intGetdif (intXinty);Ten intMain () One { A     intA, B; -cout <<"Please input the integer:"; -Cin>>a >>b; the  -Cout<<commondivisor (b) <<Endl; -Cout<<commonmultiple (b) <<Endl; -cout<<"-----------------------------------"<<Endl; +Cout<<commondivisor1 (b) <<Endl; -Cout<<commonmultiple2 (b) <<Endl; +  Acout<<"-----------------------------------"<<Endl; atCout<<commondivisor2 (b) <<Endl; -  -cout<<Endl; -  - } -  in intCommonDivisor1 (intXinty) - { to     //greatest common divisor must be between 1 and x and y smaller values, so a smaller value between x and Y starts looping through, finding the largest number of conventions +     intStart =x; -     if(X >y) theStart =y; *      for(inti = start; I >=1; i--) $     {Panax Notoginseng         if(x% i = =0&& y% i = =0) -             returni; the     } +     return 1; A } the  + intCommonDivisor2 (intXinty) - { $     //tossing and subtracting $     if(x%2==0&& y%2==0) -         return 2* COMMONDIVISOR2 (X/2, Y/2); -     Else the     { -         returngetdif (x, y);Wuyi     } the } -  Wu intGetdif (intXinty) - { About     intlarger =x; $     intsmaller =y; -     if(X <y) -     { -larger =y; Asmaller =x; +     } the     intdif = larger-smaller; -     if(DIF = =smaller) $         returndif; the     Else the         returngetdif (smaller, dif); the } the  - intCommondivisor (intXinty) in { the     //Euclidean Method the     if(x==0) About         returny; the     returnCommondivisor (y%x, x); the } the intCommonmultiple (intXinty) + { -     //least common multiple is the value of x and Y multiplied by the greatest common divisor of x and y . the     intcd =commondivisor (x, y);Bayi     return((x * y)/CD); the } the intCommonMultiple2 (intXinty) - { -     //least common multiple is a value that must be between the greater of X and Y and the XY product, so a small-to-large traversal finds this number the     intStart =x; the     intend = x *y; the     if(X <y) theStart =y; -      for(inti = y; Y <= end; i++) the     { the         if(i% x = =0&& I% y = =0) the             returni;94     } the     returnend; the}

Greatest common divisor and least common multiple algorithm implementation