Submission #922816

#	Time	Username	Problem	Language	Result	Execution time	Memory
922816		phoenix0423	Remittance (JOI19_remittance)	C++17	100 / 100	600 ms	36428 KiB

remittance

#include<bits/stdc++.h>
using namespace std;
typedef long long ll;
typedef pair<int, int> pll;
#define fastio ios::sync_with_stdio(false), cin.tie(0)
#define pb push_back
#define eb emplace_back
#define f first
#define s second
#define int long long
const int INF = 1e12;

signed main(void){
    // fastio;
    int n;
    cin>>n;
    vector<int> a(n), b(n);
    for(int i = 0; i < n; i++){
        int x, y;
        cin>>x>>y;
        a[i] = x - y;
        b[i] = y;
    }
    for(int i = 0; i < n; i++){
        if(a[i] < 0){
            int nd = - a[i] * 2;
            a[i] = 0;
            int id = (i - 1 + n) % n;
            while(id != i && a[id] < nd && nd < INF){
                if(a[id] > 0) nd -= a[id], a[id] = 0;
                nd *= 2;
                id = (id - 1 + n) % n;
            }
            if(a[id] < nd){
                cout<<"No\n";
                return 0;
            }
            a[id] -= nd;
        }
    }
    int non = 0;
    for(int i = 0; ; i = (i + 1) % n){
        if(non >= n) break;
        if(a[i] <= 0){
            non++;
            continue;
        }
        if(a[i] % 2 == 0){
            non = 0;
            a[(i + 1) % n] += a[i] / 2;
            a[i] = 0;
            continue;
        }
        if(b[i] > 0){
            non = 0;
            a[(i + 1) % n] += (a[i] / 2) + 1;
            a[i] = -1;
            continue;
        }
        non++;
    }
    for(auto x : a){
        if(x != 0){
            cout<<"No\n";
            return 0;
        }
    }
    cout<<"Yes\n";
}

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