Submission #637359

#	Time	Username	Problem	Language	Result	Execution time	Memory
637359		tvladm2009	Subway (info1cup19_subway)	C++14	100 / 100	8 ms	768 KiB

subway

#include <bits/stdc++.h>

using namespace std;

typedef long long ll;
typedef long double ld;

int k;

int main() {
    ios_base::sync_with_stdio(false);
    cin.tie(0);
    cout.tie(0);

    cin >> k;
    int n = 1;
    while (n * (n - 1) / 2 < k) {
        n++;
    }
    if (n * (n - 1) / 2 == k) {
        cout << n << "\n";
        for (int i = 0; i < n; i++) {
            cout << i << " " << i - 1 << "\n";
        }
    } else {
        n--;
        cout << n + 1 << "\n";
        for (int i = 0; i < n; i++) {
            cout << i << " " << i - 1 << "\n";
        }
        cout << n << " " << k - n * (n - 1) / 2 - 1 << "\n";
    }
    
    return 0;
}

• Subtask 1: 20 / 20
• Subtask 2: 30 / 30
• Subtask 3: 50 / 50