GCD and LCM
Time Limit: 2000/1000 MS (Java/Others) Memory Limit: 65535/65535 K (Java/Others) Total Submission(s): 78 Accepted Submission(s): 43
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
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liuyiding
很明显,m/n!=0的话,就直接输出0就可以了!否刚,直接分解质因数m/n,找到,每个质因子的个数,这样,我们,就可以得出每个质因数为a1^k1,那是题目就是要把这k1个a1分到三个数中,那么排列组合就是k1*A(3,2),也就是,6*k1,种,直接算出来就行了!
#include#include #include #include #include using namespace std;#define MAXN 100000int num[MAXN];int main(){ int tcase,n,m,i,ans,sum,tempm; scanf("%d",&tcase); while(tcase--) { scanf("%d%d",&n,&m); memset(num,0,sizeof(num)); if(m%n!=0) { printf("0\n"); continue; } m=m/n;tempm=sqrt(m)+1; for(i=2,ans=0;i<=tempm;i++) { if(m%i==0) { while(m%i==0) { num[ans]++;m/=i; } ans++; } } if(m!=1) num[ans++]=1; for(sum=1,i=0;i