HDOJ 4497 GCD and LCM

组合数学

GCD and LCM

Time Limit: 2000/1000 MS (Java/Others)    Memory Limit: 65535/65535 K (Java/Others)
Total Submission(s): 451    Accepted Submission(s): 216

Problem Description

Given two positive integers G and L, could you tell me how many solutions of (x, y, z) there are, satisfying that gcd(x, y, z) = G and lcm(x, y, z) = L? 
Note, gcd(x, y, z) means the greatest common divisor of x, y and z, while lcm(x, y, z) means the least common multiple of x, y and z. 
Note 2, (1, 2, 3) and (1, 3, 2) are two different solutions.

 

Input

First line comes an integer T (T <= 12), telling the number of test cases. 
The next T lines, each contains two positive 32-bit signed integers, G and L. 
It’s guaranteed that each answer will fit in a 32-bit signed integer.

 

Output

For each test case, print one line with the number of solutions satisfying the conditions above.

 

Sample Input

2

6 72

7 33

 

Sample Output

72

0

 

Source

2013 ACM-ICPC吉林通化全国邀请赛——题目重现

 

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#include <iostream>
#include <cstdio>
#include <cstring>

using namespace std;

int main()
{
    int t,L,G;
    scanf("%d",&t);
    while(t--)
    {
        scanf("%d%d",&G,&L);
        if(L%G!=0)
        {
            puts("0");
            continue;
        }
        int sk=L/G;
        int pp=2,ans=1,cnt;
        while(sk!=1)
        {
            cnt=0;
            while(sk%pp==0)
            {
                cnt++;
                sk/=pp;
            }
            pp++;
            if(cnt!=0)
            {
                ans*=cnt*6;
            }
        }
        printf("%d
",ans);
    }
    return 0;
}