只需A的全部质因数包含在B中即可。

#include <iostream>
#include <cstdio>
#define LL __int64
#include <algorithm>
using namespace std;


LL gcd(LL a,LL b){
	if (b==0)
	return a;
	return gcd(b,a%b);
}

int main(){
	int T,kase=0;
	LL A,B;
	scanf("%d",&T);
	while(T--){
		scanf("%I64d%I64d",&A,&B);
		LL g=gcd(A,B);
		LL t=A/g;
		LL tmp=gcd(g,t);
		while(1!=tmp){
			t/=tmp;
			tmp=gcd(g,t);
		}
		if(t==1)
		printf("Case #%d: YES\n",++kase);
		else printf("Case #%d: NO\n",++kase);
	}
}