Submission #1104206

#	Time	Username	Problem	Language	Result	Execution time	Memory
1104206		nasir_bashirov	Feast (NOI19_feast)	C++11	100 / 100	216 ms	15176 KiB

feast

// #pragma GCC optimize("O3,unroll-loops")
// #pragma GCC target("avx2,bmi,bmi2,lzcnt,popcnt")

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

#define ll long long
#define pii pair<int, int>
#define pll pair<ll, ll>
#define vi vector<int>
#define vl vector<ll>
#define vii vector<pii>
#define db long double
#define vll vector<pll>
#define endl '\n'
#define all(x) x.begin(), x.end()
#define fastio ios_base::sync_with_stdio(0); cin.tie(0); cout.tie(0);

#define int long long

const int sz = 3e5 + 5;
int n, k, a[sz];
pii dp[sz][2];

void calc(int mid){
    dp[1][0] = {0, 0}, dp[1][1] = {a[1] - mid, 1};
    for(int i = 2; i <= n; i++){
        dp[i][0] = max(dp[i - 1][0], dp[i - 1][1]);
        dp[i][1] = max(make_pair(dp[i - 1][0].first + a[i] - mid, dp[i - 1][0].second + 1), make_pair(dp[i - 1][1].first + a[i], dp[i - 1][1].second));
    }
}

void fmain(){
    cin >> n >> k;
    for(int i = 1; i <= n; i++){
        cin >> a[i];
    }
    int l = 0, r = 1e15, res = 0;
    while(l <= r){
        int mid = (l + r) / 2;
        calc(mid);
        if(max(dp[n][0], dp[n][1]).second >= k){
            l = mid + 1;
            res = mid;
        } 
        else{
            r = mid - 1;
        }
    }
    calc(res);
    cout << res * k + max(dp[n][0], dp[n][1]).first;
}

signed main(){
    int tmr = 1;
    //cin >> tmr;
    while(tmr--){
        fmain();
    }
}

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