nyoj-111

分类讨论没有考虑仔细

#include<iostream>#include<fstream>#include<string.h>using namespace std;int gcd(int a,int b){return b==0?a:gcd(b,a%b);}int main(){string s;//fstream cin("d:\\test.txt");while(!cin.eof() && cin>>s){int a,b,c,d,t1,t2,g;char ch;a=s[0]-'0';b=s[2]-'0';ch=s[3];c=s[4]-'0';d=s[6]-'0';if(ch=='+'){t1=a*d+b*c;t2=b*d;g=gcd(t1,t2);t1/=g;t2/=g;if(t1==t2)cout<<1<<endl;else if(t1==0 || t2==1)cout<<t1<<endl;elsecout<<t1<<"/"<<t2<<endl;}else if(ch=='-'){t1=a*d-b*c;t2=b*d;if(t1<0)g=gcd(-t1,t2);elseg=gcd(t1,t2);t1/=g;t2/=g;if(t1==t2)cout<<1<<endl;else if(t1==0 || t2==1)cout<<t1<<endl;else cout<<t1<<"/"<<t2<<endl;}}return 0;}