Submission #1019403

#	Time	Username	Problem	Language	Result	Execution time	Memory
1019403		Nicolaikrob	Feast (NOI19_feast)	C++17	100 / 100	198 ms	10508 KiB

feast

#include <bits/stdc++.h>
using namespace std;
typedef long long ll;
const ll inf = 1LL<<50;

ll n, k;
vector<ll> PS, DP, C;

ll sol(ll g) {
    ll b = PS[n], c = 0;
    for(int i = 1; i <= n; i++) {
        if(DP[i-1] >= b-(PS[n]-PS[i])-g)
            DP[i] = DP[i-1],
            C[i] = C[i-1];
        else
            DP[i] = b-(PS[n]-PS[i])-g,
            C[i] = c+1;

        if(b < DP[i]+PS[n]-PS[i])
            b = DP[i]+PS[n]-PS[i], c = C[i];
    }
    return C[n];
}

int main() {
    cin >> n >> k;
    PS.resize(n+1, 0);
    DP.resize(n+1, 0);
    C.resize(n+1, 0);
    for(int i = 1; i <= n; i++)
        cin >> PS[i], PS[i] += PS[i-1];
    ll l = 0, u = inf;
    while(l < u) {
        ll g = (l+u)/2;
        ll c = sol(g);
        if(c == k) l = u = g;
        if(c > k) l = g;
        if(c < k) u = g;
    }
    sol(l);
    cout << DP[n]+k*l;
}

• 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