Submission #1354454

#	Time	Username	Problem	Language	Result	Execution time	Memory
1354454		fggg	송금 (JOI19_remittance)	C++20	0 / 100	0 ms	348 KiB

remittance

#include <bits/stdc++.h>
using namespace std;
using ll = long long;

void solve() {
    ll n;
    cin >> n;
    vector<ll> a(n), b(n);
    ll sa = 0, sb = 0;
    for (ll i = 0; i < n; i++) {
        cin >> a[i] >> b[i];
        sa += a[i];
        sb += b[i];
    }
    if (sa < sb) {
        cout << "No";
        return;
    }
    while (1) {
        ll c = 1;
        for (ll i = 0; i < n; i++) c &= (a[i] == b[i]);
        if (c) {
            cout << "Yes";
            return;
        }
        bool f = false;
        for (ll i = 0; i < n; i++) {
            if (a[i] > b[i] && a[i] != 1) {
                ll x = (a[i] - b[i] + 1) / 2;
                if (i != n - 1) {
                    //cout << x << '\n';
                    a[i] -= 2 * x;
                    a[(i + 1) % n] += x;
                } else {
                    if (a[0] + x - 1 <= b[0]) {
                        a[n - 1] -= 2 * x;
                        a[0] += x;
                    } else {
                        a[n - 1] -= 2 * (a[0] - b[0] + 1);
                        a[0] = b[0] + 1;
                    }
                }
                f = true;
                break;
            }
        }
        if (!f) break;
    }
    cout << "No";
}

signed main() {
    cin.tie(nullptr);
    ios_base::sync_with_stdio(false);
    ll t = 1;
    //cin >> t;
    while (t--) {
        solve();
    }
    return 0;
}

• Subtask 1: 0 / 15
• Subtask 2: 0 / 40
• Subtask 3: 0 / 45