Submission #370410

#	Time	Username	Problem	Language	Result	Execution time	Memory
370410		daniel920712	Bigger segments (IZhO19_segments)	C++14	37 / 100	310 ms	93292 KiB

segments

#include <iostream>
#include <stdio.h>
#include <stdlib.h>
#include <algorithm>

using namespace std;
long long all[500005];
long long DP[3005][3005];
long long big[3005][3005];
bool have[3005][3005]={0};
long long sum[500005]={0},N;

long long F(long long a,long long b)
{
    long long i;
    if(b==N) return 1;
    if(have[a][b]) return DP[a][b];
    have[a][b]=1;
    for(i=b+1;i<=N;i++)
    {
        if(sum[i]-sum[b]>=sum[b]-sum[a]) DP[a][b]=max(DP[a][b],F(b,i)+1);
    }
    return DP[a][b];
}
int main()
{
    long long i,j,k,ans=0;
    scanf("%lld",&N);
    for(i=1;i<=N;i++)
    {
        scanf("%lld",&all[i]);
        sum[i]=all[i]+sum[i-1];
    }
    for(i=N;i>=0;i--)
    {
        big[i][N+1]=-1e18;
        for(j=N;j>i;j--)
        {
            DP[i][j]=-1e18;
            if(j==N) DP[i][j]=1;
            else
            {
                k=lower_bound(sum+1,sum+N+1,2*sum[j]-sum[i])-sum;
                DP[i][j]=big[j][k]+1;
                //printf("%lld %lld %lld %lld\n",i,j,k,DP[i][j]);
            }
            big[i][j]=max(big[i][j+1],DP[i][j]);
        }

    }
    for(i=1;i<=N;i++) ans=max(ans,DP[0][i]);
    printf("%lld\n",ans);
    return 0;
}

Compilation message (stderr)

segments.cpp: In function 'int main()':
segments.cpp:28:10: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
   28 |     scanf("%lld",&N);
      |     ~~~~~^~~~~~~~~~~
segments.cpp:31:14: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
   31 |         scanf("%lld",&all[i]);
      |         ~~~~~^~~~~~~~~~~~~~~~

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