c语言输入两个整数求最小公倍数

Question

说明：两个整数可以是正数、零和负数。最小公倍数必须是自然数。题目保证两个整数及其最小公倍数的绝对值都小于 2 ^63

输入样例1
935761 -5128800173759
输出样例1
4799331179396895599
输入样例2
-4187757414530339 587895547746
输出样例2
929682146025735258
输入样例3
7 0
输出样例3
0
输入样例4
0 0
输出样例4
0

Answer 1

#include <stdio.h>

void swap(long long *a, long long *b)
{
    long long t = *a;
    *a = *b;
    *b = t;
}

long long gcd(long long a, long long b)
{
    if (a > b)
        swap(&a, &b);
    long long r = b % a;
    if (r == 0)
        return a;
    return gcd(r, a);
}

long long lcm(long long a, long long b)
{
    if (a == 0 || b == 0)
        return 0;
    if (a < 0)
        a = -a;
    if (b < 0)
        b = -b;
    long long d = gcd(a, b);
    return a / d * b;
}

int main()
{
    long long a, b;
    scanf("%lld%lld", &a, &b);
    printf("%lld", lcm(a, b));
    return 0;
}