Submission #31757

#	Time	Username	Problem	Language	Result	Execution time	Memory
31757		aome	K blocks (IZhO14_blocks)	C++14	100 / 100	373 ms	4172 KiB

blocks

#include <bits/stdc++.h>
#define fi first
#define se second
using namespace std;

typedef pair<int, int> ii;
typedef pair<int, ii> p;
const int N = 100005;
const int INF = 1e9;

int n, k, f[2][N], a[N];

int main() {
//    freopen("in.txt", "r", stdin);
//    freopen("out.txt", "w", stdout);
    ios::sync_with_stdio(false);
    cin >> n >> k;
    for (int i = 1; i <= n; ++i) cin >> a[i];
    for (int i = 1; i <= n; ++i) f[0][i] = INF;
    for (int i = 1; i <= k; ++i) {
        bool t = i & 1;
        stack<p> st[2];
        f[t][0] = INF;
        for (int j = 1; j <= n; ++j) {
            int pos = j;
            int val = f[t ^ 1][j - 1];
            while (st[0].size() && a[st[0].top().fi] <= a[j]) {
                pos = st[0].top().se.fi;
                val = min(val, st[0].top().se.se);
                st[0].pop();
            }
            st[0].push(p(j, ii(pos, val)));
            while (st[1].size() && st[1].top().se.fi >= pos) st[1].pop();
            if (!(st[1].size() && st[1].top().se.se <= val + a[j])) {
                st[1].push(p(j, ii(pos, val + a[j])));
            }
            f[t][j] = st[1].top().se.se;
            //cout << pos << ' ' << val << ' ' << f[t][j] << ' ' << j << '\n';
        }
    }
    cout << f[k & 1][n];
}

• Subtask 1: 14 / 14
• Subtask 2: 18 / 18
• Subtask 3: 21 / 21
• Subtask 4: 47 / 47