Submission #1134586

#	Time	Username	Problem	Language	Result	Execution time	Memory
1134586		Luvidi	Feast (NOI19_feast)	C++17	100 / 100	143 ms	12168 KiB

feast

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

#define ll long long
#define pll pair<ll, ll>
#define pii pair<int, int>
#define fs first
#define sc second
#define pb push_back

void solve() {
    int n,k;
    cin>>n>>k;
    ll a[n+1];
    for(int i=1;i<=n;i++)cin>>a[i];
    auto calc=[&](ll x){
        pll dp[n+1][2];
        dp[0][0]={0,0};
        dp[0][1]={-1e18,0};
        for(int i=1;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].fs-x,dp[i-1][0].sc+1),dp[i-1][1]);
            dp[i][1].fs+=a[i];
        }
        return max(dp[n][0],dp[n][1]);
    };
    ll l=0,r=1e18;
    while(l<r){
        ll m=(l+r+1)/2;
        if(calc(m).sc>=k)l=m;
        else r=m-1;
    }
    cout<<calc(l).fs+l*k<<'\n';
}

int main() {
    #ifdef FPO
        freopen("in","r",stdin);
        freopen("out","w",stdout);
    #endif
    ios_base::sync_with_stdio(0); cin.tie(0); cout.tie(0);

    solve();
}

• 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