Submission #897776

#	Time	Username	Problem	Language	Result	Execution time	Memory
897776		CDuong	Feast (NOI19_feast)	C++17	4 / 100	93 ms	10592 KiB

feast

/*
#pragma GCC optimize("Ofast,unroll-loops")
#pragma GCC target("avx2,fma,bmi,bmi2,sse4.2,popcnt,lzcnt")
*/

#include <bits/stdc++.h>
#define taskname ""
#define all(x) x.begin(), x.end()
#define rall(x) x.rbegin(), x.rend()
#define i64 long long
#define int long long
#define pb push_back
#define ff first
#define ss second
#define isz(x) (int)x.size()
using namespace std;

const int mxN = 3e5 + 5;
const int mod = 1e9 + 7;
const i64 oo = 1e18;

int n, k;
i64 a[mxN];
pair<int, int> dp[mxN];

pair<int, int> calc(i64 delta) {
    pair<int, int> mx = {0, 0}, res = {0, 0};
    for (int i = 1; i <= n; ++i) {
        int tmp = mx.ff + a[i] + delta;
        dp[i] = max(dp[i - 1], pair{tmp, mx.ss - 1});
        mx = max(mx, pair{dp[i].ff - a[i], mx.ss});
        res = max(res, dp[i]);
    }
    // cout << mx.ff << " " << mx.ss << endl;
    return res;
}

void solve() {
    cin >> n >> k;
    for (int i = 1; i <= n; ++i) {
        cin >> a[i];
        a[i] += a[i - 1];
    }
    i64 l = -1e12, r = 0;
    while (l < r) {
        int mid = (l + r + 1) >> 1;
        if (calc(mid).ss <= k) l = mid;
        else r = mid - 1;
    }
    auto res = calc(l);
    cout << res.ff + res.ss * l << endl;
}

signed main() {

#ifndef CDuongg
    if(fopen(taskname".inp", "r"))
        assert(freopen(taskname".inp", "r", stdin)), assert(freopen(taskname".out", "w", stdout));
#else
    freopen("bai3.inp", "r", stdin);
    freopen("bai3.out", "w", stdout);
    auto start = chrono::high_resolution_clock::now();
#endif

    ios_base::sync_with_stdio(false);
    cin.tie(nullptr);
    int t = 1; //cin >> t;
    while(t--) solve();

#ifdef CDuongg
   auto end = chrono::high_resolution_clock::now();
   cout << "\n"; for(int i = 1; i <= 100; ++i) cout << '=';
   cout << "\nExecution time: " << chrono::duration_cast<chrono::milliseconds> (end - start).count() << "[ms]" << endl;
   cout << "Check array size pls sir" << endl;
#endif

}

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