poj 3992 Tiles of Tetris, NOT!

#include<stdio.h>long long a,b;long long up(long long a,long long b){long long t;if(a==0) return b;while(b!=0){t=b;b=a%b;a=t;}return a;}int main(){while(scanf("%lld%lld",&a,&b)!=EOF){if(a==0&&b==0) break;printf("%lldn",a*b/up(a,b)/up(a,b));        }        return 0;}