Submission #55330

#	Time	Username	Problem	Language	Result	Execution time	Memory
55330		ksun48	Sparklers (JOI17_sparklers)	C++14	50 / 100	23 ms	5100 KiB

sparklers

#include <bits/stdc++.h>
using namespace std;
typedef long long LL;

int main(){
	cin.sync_with_stdio(0); cin.tie(0);
	LL n, k, t;
	cin >> n >> k >> t;
	k--;
	vector<LL> x(n);
	for(int i = 0; i < n; i++){
		cin >> x[i];
	}		
	LL s = -1;
	LL e = 1000000000;
	LL dp[n][n];
	while(s + 1 < e){
		LL m = (s + e) / 2;
		vector<LL> y = x;
		for(LL i = 0; i < n; i++){
			y[i] -= m * t * 2 * i;
		}
		for(LL i = k; i >= 0; i--){
			for(LL j = k; j < n; j++){
				dp[i][j] = 0;
				if(y[j] <= y[i]){
					if((i == k && j == k) || (i < k && dp[i+1][j]) || (j > k && dp[i][j-1])){
						dp[i][j] = 1;
					}
				}
			}
		}
		if(dp[0][n-1]){
			e = m;
		} else {
			s = m;
		}
	}
	cout << e << '\n';
}

• Subtask 1: 30 / 30
• Subtask 2: 20 / 20
• Subtask 3: 0 / 50