Submission #41091

#	Time	Username	Problem	Language	Result	Execution time	Memory
41091		IvanC	Stove (JOI18_stove)	C++14	100 / 100	35 ms	3056 KiB

stove

#include <bits/stdc++.h>
using namespace std;
typedef long long ll;
typedef pair<ll,ll> ii;
const int MAXN = 1e5 + 10;
ll vetor[MAXN],N,K;
ii dp[MAXN];
ii solve(ll W){
	dp[0] = ii(0,0);
	ii best = ii(-vetor[1] + 1,0);
	for(ll i = 1;i<=N;i++){
		dp[i] = ii(best.first + vetor[i] + W,best.second - 1);
		best = min(best, ii(-vetor[i+1] + 1 + dp[i].first,dp[i].second) );
	}
	return dp[N];
}

int main(){
	cin.tie(0);ios_base::sync_with_stdio(0);
	cin >> N >> K;
	for(ll i = 1;i<=N;i++) cin >> vetor[i];
	ll ini = 0, fim = (ll)2*1e9, resp = -1,meio;
	while(ini <= fim){
		meio = (ini+fim)/2;
		if(abs(solve(meio).second) >= K){
			resp = meio;
			ini = meio + 1;
		}
		else{
			fim = meio - 1;
		}
	}
	cout << solve(resp).first - K*resp << endl;
	return 0;
}

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