Submission #885580

#	Time	Username	Problem	Language	Result	Execution time	Memory
885580		kokoue	Bigger segments (IZhO19_segments)	C++14	0 / 100	1 ms	2396 KiB

segments

#include<bits/stdc++.h>
#define MAXN 500010
using namespace std;
long long a[MAXN];
long long pre[1000000];
int n;
int binary(int l,int goal)
{
    int r=n;
    int start=l;
    int mid;
    while(l!=r)
    {
        mid=(l+r)/2;
        if(pre[mid]-pre[start]==goal) return mid;
        if(pre[mid]-pre[start]<goal)
        {
            l=mid+1;
        }
        else r=mid;
    }
    return r;
}
int dfs(int curr, long long sum, int cntr)
{
 //   printf("idx%d = %d; ",cntr,curr);
    if(curr>n) return 0;
  //  printf("in curr=%d,sum=%d,cntr=%d\n ",curr,sum,cntr);
    long long nsum=0;
    int ans=cntr;
    ans=max(ans,dfs(curr+1,sum+a[curr+1],cntr));
    int idx=binary(curr,sum);
    if(idx!=curr)
    {
  //      printf("idx%d = %d ",cntr,idx);
        ans=max(ans,dfs(idx,pre[idx]-pre[curr-1],cntr+1));
       // ans=max(ans,dfs(idx+1,pre[idx+1]-pre[curr-1],cntr+1));
    }
   // printf("\n");
  //  printf("in curr=%d,sum=%d,cntr=%d -> ans=%d\n",curr,sum,cntr,ans);
    return ans;
}
int main()
{
    ios_base::sync_with_stdio(false);
    cin.tie(0);
    cin>>n;
    for(int i=1;i<=n;i++)
    {
        cin>>a[i];
        pre[i]=pre[i-1]+a[i];
    }
    cout<<dfs(1,a[1],1)<<"\n";
}

Compilation message (stderr)

segments.cpp: In function 'int dfs(int, long long int, int)':
segments.cpp:29:15: warning: unused variable 'nsum' [-Wunused-variable]
   29 |     long long nsum=0;
      |               ^~~~

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