Submission #588017

#	Time	Username	Problem	Language	Result	Execution time	Memory
588017		sofapuden	Feast (NOI19_feast)	C++14	18 / 100	154 ms	26736 KiB

feast

#include<bits/stdc++.h>

using namespace std;

typedef long long ll;

ll mn = -(1ll<<60);

void solve(){
	int n, k; cin >> n >> k;
	vector<ll> v(n);
	for(auto &x : v)cin >> x;
	ll l = 0, r = (1ll<<42), bes = 0;
	vector<vector<pair<ll,ll>>> dp(n,vector<pair<ll,ll>>(2));
	while(l<=r){
		ll m = (l+r)>>1;
		dp[0][0] = {0,0};
		dp[0][1] = {-m+v[0],1};
		for(int i = 1; i < n; ++i){
			dp[i][0] = max(dp[i-1][0],dp[i-1][1]);
			dp[i][1] = max(dp[i-1][1],{dp[i-1][0].first-m,dp[i-1][0].second+1});
			dp[i][1].first+=v[i];
		}
		pair<ll,ll> b = max(dp[n-1][0], dp[n-1][1]);
		if(b.second >= k){
			bes = b.first + m*k;
			l = m+1;
		}
		else{
			r = m-1;
		}
	}
	cout << bes << '\n';
}

int main(){
	ios_base::sync_with_stdio(0); cin.tie(0); cout.tie(0);
	solve();
}

• Subtask 1: 0 / 4
• Subtask 2: 0 / 8
• Subtask 3: 18 / 18
• Subtask 4: 0 / 10
• Subtask 5: 0 / 11
• Subtask 6: 0 / 20
• Subtask 7: 0 / 29