HDU 5810 Balls and Boxes

n*(m-1)/(m*m)

#pragma comment(linker, "/STACK:1024000000,1024000000")
#include<cstdio>
#include<cstring>
#include<cmath>
#include<algorithm>
#include<vector>
#include<map>
#include<set>
#include<queue>
#include<stack>
#include<iostream>
using namespace std;
typedef long long LL;
const double pi=acos(-1.0),eps=1e-8;
void File()
{
    freopen("D:\\in.txt","r",stdin);
    freopen("D:\\out.txt","w",stdout);
}
inline int read()
{
    char c = getchar(); while(!isdigit(c)) c = getchar(); int x = 0;
    while(isdigit(c)) { x = x * 10 + c - '0'; c = getchar();  }
    return x;
}

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

int main()
{
    while(~scanf("%lld%lld",&n,&m))
    {
        if(n==0&&m==0) break;
        LL x1=n*(m-1),x2=m*m ;
        LL GCD=gcd(x1,x2);
        if(x1==0) printf("0/1\n");
        else printf("%lld/%lld\n",x1/GCD,x2/GCD);
    }
    return 0;
}