c++编译

#include <iostream>
#include <stdio.h>
#include <stdlib.h>

using namespace std;
struct Fraction{
    
    
    int up,down;
};
int gcd(int a,int b){
    
    
    while(b!=0){
    
    
        int r=b;
        b=a%b;
        a=r;
    }
    return a;
}

Fraction reduction(Fraction result){
    
    
    int d=gcd(abs(result.up),abs(result.down));
    result.up/=d;
    result.down/=d;
    return result;
}
Fraction addandminu(char str[]){
    
    
    Fraction result;
    if(str[3]=='+'){
    
    
        result.up=(str[0]-'0')*(str[6]-'0')+(str[4]-'0')*(str[2]-'0');
        result.down=(str[2]-'0')*(str[6]-'0');
        return reduction(result);
    }
    else{
    
    
        result.up=(str[0]-'0')*(str[6]-'0')-(str[4]-'0')*(str[2]-'0');
        result.down=(str[2]-'0')*(str[6]-'0');
        return reduction(result);
    }
}
int main()
{
    
    
    char str[8];
    Fraction res;
    while(scanf("%s",str)!=EOF){
    
    
            res=addandminu(str);
        if(res.up==0)
            cout<<0<<endl;
        else if(res.down==1)
            cout<<res.up<<endl;
        else
            cout<<res.up<<"/"<<res.down<<endl;
    }
    return 0;
}

注释：首先不要忘记给得到的分数进行化简，分子为0时，直接输出0。分母为1时直接输出分子。