原来写的找了好久还是有一个测试点没过， 虽说是道水题，但是今天一遍就过了还是挺高兴的。

送你机组数据

5

2/5 4/15 1/30 -2/60 8/3

2

4/3 2/3

3

1/3 -1/6 1/8

1

-60/12

2

-1/2 1/3

1

0/1021

2

0/1 0/12

1

-1/1

1

6/6

#********************************************************************************************

#include <stdio.h>

#include <string.h>

#include <iostream>

#include <math.h>

#define maxn 110

using namespace std;

typedef long long int ll;

 

ll n, a, b, sumx, sumy;

ll lcm(ll x, ll y){

if(x == y)

  return 1;

  else

  return y == 0 ? x : (lcm(y, x%y));

}

void add(ll x, ll y){

      ll temp = lcm(y, sumy);

      temp = y / temp * sumy;

      x *= temp / y;

      sumx *= temp / sumy;

      sumx += x;

      sumy = temp;

      if(sumx < 0){

      ll te = lcm(-sumx , sumy);

      sumx /= te;

      sumy /= te;

}else{

      ll te = lcm(sumx , sumy);

      sumx /= te;

      sumy /= te;

         }

     return ;

}

int main(){

 

scanf("%d", &n);

sumx = 0;

sumy = 1;

for(int i=0; i<n; ++i){

     scanf("%lld/%lld", &a, &b);

     add(a, b);

}

 

if(sumx == 0){

   cout << "0" << endl;

}else{

  int inter = sumx / sumy;

  if(inter == 0){

  cout << sumx << "/" << sumy << endl;

}else{

  cout << inter;

  if(sumx - inter * sumy > 0){

     cout << " " << sumx - inter * sumy << "/" << sumy;

  }

  cout << endl;

}

}

 

return 0;

}