数学趣题——求两个数的最大公约数和最小公倍数

   1: #include <stdio.h>

   2:  

   3: int Gcd(int a, int b)

   4: {

   5:     int min;

   6:     if (a <= 0 || b <= 0)

   7:         return -1;

   8:     if (a > b)

   9:         min = b;

  10:     else

  11:         min = a;

  12:  

  13:     while (min)

  14:     {

  15:         if (a % min == 0 && b % min == 0)

  16:             return min;

  17:  

  18:         min --;

  19:     }

  20:  

  21:     return -1;

  22: }

  23:  

  24: int Lcm(int a, int b)

  25: {

  26:     int max;

  27:     if (a <= 0 || b <= 0)

  28:         return -1;

  29:     if (a > b)

  30:         max = a;

  31:     else

  32:         max = b;

  33:  

  34:     while (max)

  35:     {

  36:         if (max % a == 0 && max % b == 0)

  37:             return max;

  38:  

  39:         max++;

  40:     }

  41:  

  42:     return -1;

  43: }

  44:  

  45: int main()

  46: {

  47:     int a, b;

  48:     printf("Input a b\n");

  49:     scanf("%d %d", &a, &b);

  50:  

  51:     printf("the gcd is %d\n", Gcd(a, b));

  52:     printf("the lcm is %d\n", Lcm(a, b));

  53:     return 0;

  54: }