#include <iostream>using namespace std;int gy(int a,int k1){int min;if(a>k1)min=k1;else min=a; while(min) { if(a%min==0&&k1%min==0) {if(k1/min==1) cout<<a/min<<endl; else cout<<a/min<<‘/‘<<k1/min<<endl; break; } min--; }return 0;}int main(){int a,b,c,d,k1,g; char x1,j1,j2; while(cin>>a>>j1>>b>>x1>>c>>j2>>d) {k1=b*d; a=a*d;c=b*c; if(x1==‘-‘) {a=a-c; if(a==0) cout<<‘0‘<<endl; if(a<0){a=-a;cout<<"-";gy(a,k1);} else {gy(a,k1);} } if(x1==‘+‘) {a=c+a; if(a==0) cout<<‘0‘<<endl; else gy(a,k1); }} cout<<endl;return 0;}原文：http://www.cnblogs.com/lxh-boke/p/4537206.html