题解 | 【模板】分数四则运算

#include <iostream>
#include <cmath>
using namespace std;
long long gcd(long long a, long long b) {
    a = abs(a);
    b = abs(b);
    while (b != 0) {
        long long t = b;
        b = a % b;
        a = t;
    }
    return a;
}
void G(long long& a, long long& b) {
    if (b == 0) {
        if (a == 0) {
            cout << "nan" << endl;
        } else {
            cout << "inf" << endl;
        }
        return;
    }
    long long g = gcd(a, b);
    if (g == 0) {
        cout << "0 1" << endl;
        return;
    }
    a /= g;
    b /= g;
    if (b < 0) {
        a = -a;
        b = -b;
    }
    cout << a << " " << b << endl;
}
int main() {
    ios::sync_with_stdio(false);
    cin.tie(nullptr);
    int t;
    cin >> t;
    while (t--) {
        long long a, b, c, d, op;
        cin >> a >> b >> op >> c >> d;
        long long m, n;
        if (op == 1) {
            m = a * d + b * c;
            n = b * d;
        } else if (op == 2) {
            m = a * d - b * c;
            n = b * d;
        } else if (op == 3) {
            m = a * c;
            n = b * d;
        } else {
            if (d == 0 || c == 0) {
                cout << "inf" << endl;
                continue;
            }
            m = a * d;
            n = b * c;
        }

        if (n == 0) {
            cout << "inf" << endl;
        } else {
            G(m, n);
        }
    }
    return 0;
}
// 64 位输出请用 printf("%lld")