Submission #1100491

#	Time	Username	Problem	Language	Result	Execution time	Memory
1100491		vjudge1	Feast (NOI19_feast)	C++17	30 / 100	158 ms	14072 KiB

feast

/*For today, you happen to be the defeated. But what will you become tomorrow?*/

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

const int N = 300005;
const ll inf = (1ll << 60);
int arr[N], n, k;
array<ll, 2> dp[N][2];

array<ll, 2> f(ll c) {
    for(int i = 0; i <= n; i ++) {
        dp[i][0] = {0, 0};
        dp[i][1] = {-inf, 0};
    }

    for(int i = 1; i <= n; i ++) {
        dp[i][0] = dp[i - 1][0];
        dp[i][1] = {dp[i - 1][1][0] + (ll)arr[i], dp[i - 1][1][1]};
        array<ll, 2> cur = {dp[i - 1][0][0] + (ll)arr[i] - c, dp[i - 1][0][1] + 1};
        dp[i][1] = max(dp[i][1], cur);
        dp[i][0] = max(dp[i][0], dp[i][1]);
        
    }
    return dp[n][0];
}
void solve() {
    
    cin >> n >> k;
    for(int i = 1; i <= n; i ++) cin >> arr[i];    
    ll lo = 0, hi = (1ll << 40), ans = 0;

    while(lo <= hi) {
        ll mid = (lo + hi) / 2;
        array<ll, 2> yo = f(mid);
        if(yo[1] >= k) {
            ans = yo[0] + k * mid;
            lo = mid + 1;
        }
        else {
            hi = mid - 1;
        }
    }

    cout << ans << '\n';
}

int32_t main() {
    ios::sync_with_stdio(0);
    cin.tie(0);
        
    int t = 1;
    // cin >> t;
    
    while(t--){
        solve();
    }

    return 0;
}

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