C练习题——打印两个数的最大公约数

算法一：暴力求解(效率不够)

#include <stdio.h>
int main()
{
    int a = 0;
    int b = 0;
    scanf("%d %d", &a, &b);
    int min = a < b ? a : b;
    while (1)
    {
        if ((a % min == 0) && (b % min == 0))
            break;
        min--;
    }
    printf("%d\n", min);
    
    
    return 0;
}

算法二优化:辗转相除法，大数对小数取余，小数再对余数取余，余数为零停，无须比较，大小自动交换 

#include <stdio.h>
int main()
{
    int a = 0;
    int b = 0;
    int c = 0;
    scanf("%d %d", &a, &b);
    while (c = a % b)
    {
        a = b;
        b = c;
    }
    printf("%d\n", b);
    return 0;
}