Submission #1192712

#	Time	Username	Problem	Language	Result	Execution time	Memory
1192712		simona1230	Aliens (IOI16_aliens)	C++20	4 / 100	0 ms	840 KiB

aliens

#include "aliens.h"
#include <bits/stdc++.h>
using namespace std;

int num;
pair<int,int> p[200001];
bool cmp(pair<int,int> p1,pair<int,int> p2)
{
    if(p1.second==p2.second)return p1.first<p2.first;
    return p1.second<p2.second;
}


long long sq(int x)
{
    return x*x;
}
long long dp[5001][4001];
long long f[5001][4001];
long long take_photos(int n, int m, int k, std::vector<int> r, std::vector<int> c)
{
    for(int i=0;i<n;i++)
        p[i]={min(r[i],c[i]),max(r[i],c[i])};
    sort(p,p+n,cmp);
    for(int i=0;i<n;i++)
    {
        if(i!=0&&p[i].second==p[i-1].second)continue;
        while(num!=0&&p[num-1].first>=p[i].first)num--;
        p[num++]=p[i];
    }

    /*cout<<num<<endl;
    for(int i=0;i<num;i++)
        cout<<p[i].first<<" "<<p[i].second<<endl;*/
    for(int i=0;i<num;i++)
    {
        for(int j=0;j<=k;j++)
        {
            dp[i][j]=1e18;
        }
    }

    long long ans=1e18;
    dp[0][1]=sq(p[0].second-p[0].first+1);
    f[0][1]=p[0].first;
    for(int i=1;i<num;i++)
    {
        dp[i][1]=sq(p[i].second-p[0].first+1);
        for(int j=1;j<=k;j++)
        {
            long long h1=dp[i-1][j-1]+sq(p[i].second-p[i].first+1);
            if(p[i].first<=p[i-1].second)h1-=sq(p[i-1].second-p[i].first+1);
            long long h2=dp[i-1][j]+sq(p[i].second-f[i-1][j]+1)-sq(p[i-1].second-f[i-1][j]+1);
            if(h1<h2)dp[i][j]=h1,f[i][j]=p[i].first;
            else dp[i][j]=h2,f[i][j]=f[i-1][j];
            //cout<<i<<" "<<j<<" "<<dp[i][j]<<endl;
            if(i==num-1)ans=min(ans,dp[i][j]);
        }
    }
    ans=min(ans,dp[num-1][1]);
    return ans;
}

Compilation message (stderr)

aliens.h:1:9: warning: #pragma once in main file
    1 | #pragma once
      |         ^~~~
aliens_c.h:1:9: warning: #pragma once in main file
    1 | #pragma once
      |         ^~~~

• Subtask 1: 4 / 4
• Subtask 2: 0 / 12
• Subtask 3: 0 / 9
• Subtask 4: 0 / 16
• Subtask 5: 0 / 19
• Subtask 6: 0 / 40