又是。。GCD;
直接附上代码了:
#include<stdio.h>
int gcd(int a,int b)
{
return (b==0?a:gcd(b,a%b));
}
int main()
{
int a,b,n,c,t;
scanf("%d",&n);
while(n--)
{
while(scanf("%d%d",&a,&b)==2)
{
c=b*2;
while(gcd(a,c)!=b)
{
c+=b;
}
printf("%d\n",c);
}
}
return 0;
}