Submission #1101633

#	Time	Username	Problem	Language	Result	Execution time	Memory
1101633		ngongocbich	K blocks (IZhO14_blocks)	C++17	100 / 100	628 ms	97916 KiB

blocks

#include <bits/stdc++.h>
#define int long long
#define mask(k) (1<<(k))
using namespace std;
int n,k,a[100001],dp[100001][101],l[100001],mx[100001][21];
stack<int> st;
int getmn(int l, int r)
{
    int p=__lg(r-l+1);
    return min(mx[l][p],mx[r-mask(p)+1][p]);
}
signed main()
{
    ios_base::sync_with_stdio(0);
    cin.tie(0); cout.tie(0);
    //freopen("kblocks.inp","r",stdin);
    //freopen("kblocks.out","w",stdout);
    cin>>n>>k;
    for (int i=1; i<=n; i++) cin>>a[i];
    for (int i=1; i<=n; i++)
    {
        while (!st.empty() && a[st.top()]<=a[i]) st.pop();
        if (!st.empty()) l[i]=st.top(); else l[i]=0;
        st.push(i);
    }
    memset(dp,0x3f,sizeof(dp));
    dp[0][0]=0;
    for (int j=1; j<=k; j++)
    {
        for (int i=0; i<=n; i++) mx[i][0]=dp[i][j-1];
        for (int j=1; mask(j)<=n+1; j++)
            for (int i=0; i+mask(j)-1<=n; i++)
                mx[i][j]=min(mx[i][j-1],mx[i+mask(j-1)][j-1]);
        for (int i=1; i<=n; i++)
        {
            dp[i][j]=min(dp[i][j],getmn(l[i],i-1)+a[i]);
            dp[i][j]=min(dp[i][j],dp[l[i]][j]);
        }
    }
    cout<<dp[n][k];
    return 0;
}

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