Submission #1219471

#	Time	Username	Problem	Language	Result	Execution time	Memory
1219471		omsincoconut	Portal (BOI24_portal)	C++17	1 / 100	12 ms	1092 KiB

Main

#include <bits/stdc++.h>

using namespace std;
typedef long long ll;

int main() {
    ios_base::sync_with_stdio(false);
    cin.tie(NULL);

    int N;
    cin >> N;

    if (N <= 2) {
        cout << -1;
        return 0;
    }

    int x[N+1], y[N+1];
    for (int i = 1; i <= N; i++) cin >> x[i] >> y[i];

    ll dx1 = x[2] - x[1], dy1 = y[2] - y[1];
    ll dx2 = x[3] - x[1], dy2 = y[3] - y[1];

    ll sx, sy;
    
    if (dy1 == 0) {
        sx = dx1;
    } else if (dy2 == 0) {
        sx = dx2;
    } else {
        ll GCD = gcd(dy1,dy2);
        sx = dy1/GCD*dx1 - dy2/GCD*dx2;
    }

    if (dx1 == 0) {
        sy = dy1;
    } else if (dx2 == 0) {
        sy = dy2;
    } else {
        ll GCD = gcd(dx1,dx2);
        sy = dx1/GCD*dy1 - dx2/GCD*dy2;
    }

    if (sx == 0 || sy == 0) cout << -1;
    else cout << abs(sx*sy);

    return 0;
}

/*
3
1 1
1 3
3 2

5
0 0
1 0
-1 0
0 1
0 -1

1
1 -1
*/

• Subtask 1: 1 / 1
• Subtask 2: 0 / 10
• Subtask 3: 0 / 10
• Subtask 4: 0 / 29
• Subtask 5: 0 / 15
• Subtask 6: 0 / 35