[模拟] P1572 计算分数

输入内容非常有规律

且EOF停止

所以循环读入整形与符形

读题 数据范围合适

所以懒

计算过程不约分

最后判正负约分

lazy算法??

//#pragma GCC optimize(2)
#include <cstdio>
#include <iostream>
#include <cstdlib>
#include <cmath>
#include <cctype>
#include <string>
#include <cstring>
#include <algorithm>
#include <stack>
#include <queue>
#include <set>
#include <map>
#include <ctime>
#include <vector>
#include <fstream>
#include <list>
#include <iomanip>
#include <numeric>
using namespace std;
typedef long long ll;

const int MAXN = 1e6 + 10;

ll gcd(ll a, ll  b)
{
    return b == 0 ? a : gcd(b, a % b);
}

int main()
{
    //ios::sync_with_stdio(false);

    //cin.tie(0);     cout.tie(0);

    char t, oprt;

    ll a, b, ansa, ansb, llt;

    cin>>ansa>>t>>ansb;

    while(cin>>oprt>>a>>t>>b)
    {
        if(b != ansb)
        {
            llt = ansb;
            ansb *= b;
            ansa *= b;
            b *= llt;
            a *= llt;  
        }

        if(oprt == '+')
            ansa += a;
        else
            ansa -= a;
    }

    llt = gcd(ansa, ansb);
    
    ansa /= llt;
    
    ansb /= llt;
    
    int mode = 0;
    
    if(ansa < 0)
    	mode ++;
    if(ansb < 0)
    	mode ++; 
    
	if(mode == 1)
		cout<<'-'; 

    ansb == 1 ? cout<<abs(ansa)<<endl : cout<<abs(ansa)<<'/'<<abs(ansb)<<endl;

    return 0;
}