#include<iostream>#include<cstdio>#include<cstring>#include<algorithm>#include<cmath>#include<queue>#include<stack>#include<vector>#include<set>#include<map>#define L(x) (x<<1)#define R(x) (x<<1|1)#define MID(x,y) ((x+y)>>1)#define eps 1e-8#define fre(i,a,b) for(i = a; i <b; i++)#define free(i,b,a) for(i = b; i >= a;i–)#define mem(t, v) memset ((t) , v, sizeof(t))#define ssf(n)scanf("%s", n)#define sf(n)scanf("%d", &n)#define sff(a,b) scanf("%d %d", &a, &b)#define sfff(a,b,c) scanf("%d %d %d", &a, &b, &c)#define pfprintf#define bugpf("Hi\n")using namespace std;typedef __int64 ll;#define INF 0x3f3f3f3f#define N 10005ll C(ll a,ll b){ll x=1,y=1;ll i;b=min(b,a-b);if(b==0) return 1;fre(i,1,b+1){x=x*a;y=y*i;a–;} return x/y;}ll fdd(ll x,ll y){if(y==0) return x;return fdd(y,x%y);}int main(){ll i,j;ll n,m;while(~scanf("%I64d%I64d",&n,&m)){j=min(n,m);ll ans=0;fre(i,1,j+1)ans=ans+i*C(n,i)*C(m,i);ll y=C(n+m,n);ll x=fdd(ans,y);pf("%I64d/%I64d\n",ans/x,y/x);}return 0;}
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