Submission #1293115

#	Time	Username	Problem	Language	Result	Execution time	Memory
1293115		haha	Bigger segments (IZhO19_segments)	C++20	37 / 100	158 ms	71096 KiB

segments

#include <bits/stdc++.h>
#define f first
#define s second
#define ll long long
using namespace std;
const int maxn=3e3+5;

int n;
int a[maxn];
int dp[maxn][maxn],Max[maxn][maxn];
ll sum[maxn];

int main()
{
    ios_base::sync_with_stdio(0);
    cin.tie(0);cout.tie(0);
    cin>>n;
    for(int i=1;i<=n;i++){
        cin>>a[i];
        sum[i]=sum[i-1]+a[i];
    }
    for(int i=0;i<=n+1;i++){
        for(int j=1;j<=n+1;j++){
            dp[i][j]=-1e9;
            Max[i][j]=-1e9;
        }
    }
    int ans=0;
    dp[1][1]=1;
    Max[1][1]=1;
    for(int i=2;i<=n;i++){
        for(int j=i;j>=1;j--){
            /*
            for(int u=1;u<j;u++){
                if(sum[i]-sum[j-1]>=sum[j-1]-sum[u-1]){
                    // sum[u-1]>=2*sum[j-1]-sum[i]
                    dp[j][i]=max(dp[j][i],dp[u][j-1]+1);
                }
            }
            */
            ll val=2*sum[j-1]-sum[i];
            int pos=lower_bound(sum,sum+j,val)-sum;
            dp[j][i]=max(dp[j][i],Max[pos+1][j-1]+1);
            //dp[j][i]=max(dp[j][i],get(1,1,n,pos+1,j-1,j-1)+1);
            //update(1,1,n,j,i,dp[j][i]);
            Max[j][i]=max(Max[j+1][i],dp[j][i]);
        }
    }
    for(int i=1;i<=n;i++) ans=max(ans,dp[i][n]);
    cout<<ans;
}

• Subtask 1: 13 / 13
• Subtask 2: 14 / 14
• Subtask 3: 10 / 10
• Subtask 4: 0 / 36
• Subtask 5: 0 / 27