Submission #1266026

#	Time	Username	Problem	Language	Result	Execution time	Memory
1266026		rayan_bd	K blocks (IZhO14_blocks)	C++20	100 / 100	233 ms	84492 KiB

blocks

#include <bits/stdc++.h>
using namespace std;
#define int long long
const int INF = 1e18;
const int mxN = 100005;
const int mxK = 105;
int a[mxN], dp[mxN][mxK], mn[mxN];

signed main(){
    ios_base::sync_with_stdio(0);
    cin.tie(nullptr); cout.tie(nullptr);

    int N, K;
    cin >> N >> K;

    for(int i = 0; i <= N; ++i){
        for(int j = 0; j <= K; ++j){
            dp[i][j] = INF;
        }
    }

    for(int i = 1; i <= N; ++i) cin >> a[i];

    for(int i = 0; i <= N; ++i) dp[i][0] = 0;

    for(int i = 1, mx = 1; i <= N; ++i){
        mx = max(mx, a[i]);
        dp[i][1] = mx;
    }

    for(int k = 2; k <= K; ++k){
        stack<int> st;
        for(int i = 1; i <= N; ++i){
            mn[i] = INF;
            while(st.size() && a[st.top()] <= a[i]){
                dp[i][k] = min(dp[i][k], dp[st.top() - 1][k - 1] + a[i]);
                mn[i] = min({mn[i], dp[st.top()][k - 1], mn[st.top()]});
                dp[i][k] = min(dp[i][k], mn[i] + a[i]);
                st.pop();
            }
            if(st.size()){
                dp[i][k] =  min(dp[i][k], dp[st.top()][k]); // extend
                dp[i][k] = min(dp[i][k], dp[st.top()][k - 1] + a[i]); // from st.top() + 1, to i
                dp[i][k] = min(dp[i][k], dp[st.top() - 1][k - 1] + a[st.top()]); // (st.top() -> i)
             //   dp[i][k] = min(dp[i][k], mn[st.top()] + a[i]); mn[i] not equal to dp[st.top()][k - 1]
            }
            dp[i][k] = min(dp[i][k], dp[i - 1][k - 1] + a[i]);
            st.push(i);
        }
    }

    cout << dp[N][K] << "\n";

    return 0;
}

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