1081. Rational Sum (20)

#include <iostream>
#include <stdio.h>
#include <algorithm>
#include <vector>
#include <math.h>
#pragma warning(disable:4996)
using namespace std;
long long int GongYue(long long int a, long long int b) {
	if (a == 0 || b == 0)
		return 1;
	if (a == b)
		return b;
	else if (a > b) {
		int m = a%b;
		while (m != 0) {
			a = b;
			b = m;
			m = a%b;
		}
		return b;
	}
	else {
		int m = b%a;
		while (m != 0) {
			b = a;
			a = m;
			m = b%a;
		}
		return a;
	}
}
vector<long long int> fenzi, fenmu;
int main(void) {
	int n;
	cin >> n;
	char temp[50];
	long long int fenzi4push,fenmu4push;
	for (int i = 0; i < n; i++) {
		scanf("%s", temp);
		sscanf(temp, "%lld/%lld", &fenzi4push, &fenmu4push);
		if (fenzi4push == 0)
			continue;
		long long int yuefen = GongYue(abs(fenzi4push), abs(fenmu4push));
		fenzi4push /= yuefen;
		fenmu4push /= yuefen;
		fenzi.push_back(fenzi4push);
		fenmu.push_back(fenmu4push);
	}
	n = fenzi.size();
	if (fenzi.size() == 0) {
		cout << "0";
		return 0;
	}
	long long int fenziResult=fenzi[0], fenmuResult=fenmu[0];
	for (int i = 1; i < n; i++) {
		if (fenmuResult == fenmu[i]) {
			fenziResult += fenzi[i];
			long long int yueshu = GongYue(abs(fenmuResult), abs(fenziResult));
			fenziResult /= yueshu;
			fenmuResult /= yueshu;
		}
		else {
			fenziResult = fenziResult*fenmu[i]+fenmuResult*fenzi[i];
			fenmuResult = fenmuResult*fenmu[i];
			long long int yueshu = GongYue(abs(fenmuResult), abs(fenziResult));
			fenziResult /= yueshu;
			fenmuResult /= yueshu;
		}
	}
	if (fenziResult*fenmuResult<0) {
		fenziResult = abs(fenziResult);
		fenmuResult = abs(fenmuResult);
		cout << "-";
	}
	if (fenziResult % fenmuResult == 0)
		cout << fenziResult / fenmuResult;
	else if (fenziResult > fenmuResult)
		cout << fenziResult / fenmuResult << " " << fenziResult % fenmuResult << "/" << fenmuResult;
	else
		cout << fenziResult << "/" << fenmuResult;
	return 0;
}