Submission #797338

#	Time	Username	Problem	Language	Result	Execution time	Memory
797338		fatemetmhr	Remittance (JOI19_remittance)	C++17	100 / 100	166 ms	16280 KiB

remittance

// Be name khoda // 
 
#include <bits/stdc++.h>
 
#define all(x) x.begin(), x.end()
#define pb     push_back
#define fi     first
#define se     second
#define mp     make_pair
 
typedef long long ll;
 
using namespace std;
 
const int maxn5 = 1e6 + 10;
const ll inf    = 1e18;
 
bool mark[maxn5];
ll a[maxn5], b[maxn5];
queue <int> q;
 
int n;
bool found = false;
 
 
void solve(int lev, int cnt){
	bool re = true;
	for(int i = 0; i < n; i++)
		re &= (a[i] == b[i]);
	if(re){
		found = true;
		return;
	}
	if(cnt == n)
		return;	
	for(int x = 2; x <= a[lev]; x+= 2){
		a[lev] -= x;
		a[(lev + 1)%n] += x / 2;
		solve((lev + 1) % n, 0);
		if(found)
			return;
		a[lev] += x;
		a[(lev + 1)%n] -= x / 2;
	}
	solve((lev + 1)%n, cnt + 1);
 
}
 
int main(){
	ios_base::sync_with_stdio(false); cin.tie(0);
 
	cin >> n;
	ll sum = 0;
	for(int i = 0; i < n; i++){
		cin >> a[i] >> b[i];
		sum += a[i];
	}
	//solve(0, 0);
	//cout << (found ? "Yes" : "No") << endl;
	//return 0;
	while(sum >= 0){
		bool re = true;
		for(int i = 0; i < n; i++){
			if(a[i] > b[i]){
				int j = (i + 1) % n;
				ll w = (a[i] - b[i]) / 2 + ((a[i] - b[i]) % 2);
                if(2 * w > a[i])
                    continue;
				a[j] += w;
				a[i] -= 2 * w;
				sum -= w;
				re = false;
			}
		}
		if(re){
			for(int i = 0; i < n; i++)
				re &= (a[i] == b[i]);
			if(!re)
				break;
			return cout << "Yes" << endl, 0;
		}
	}
	cout << "No" << endl;
 
}

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