Submission #637663

#	Time	Username	Problem	Language	Result	Execution time	Memory
637663		ggoh	Aliens (IOI16_aliens)	C++14	12 / 100	116 ms	4272 KiB

aliens

//O(n^2 k)
#include "aliens.h"
#include<bits/stdc++.h>
using namespace std;
#define sz(v) ((int)(v).size())
typedef long long lint;
typedef pair<int,int> pii;

vector<pii>Vtmp,V;
lint D[4004][4004];
lint sq(int L)
{
  return 1ll*L*L;
}
int a[100004],b[100004];
lint take_photos(int n, int m, int K, std::vector<int> r, std::vector<int> c) {
  
  for(int i=0;i<n;i++)
  {
    if(r[i]<c[i])swap(r[i],c[i]);
    Vtmp.push_back({r[i],-c[i]});
  }
  sort(Vtmp.begin(),Vtmp.end());
  int mini=1e9;
  for(int i=sz(Vtmp)-1;i>=0;i--)
  {
    if(mini>Vtmp[i].first)V.push_back({Vtmp[i].first,-Vtmp[i].second});
    mini=min(mini,-Vtmp[i].second);
  }
  sort(V.begin(),V.end());
  n=sz(V);
  for(int i=1;i<=n;i++)
  {
    a[i]=V[i-1].second+1;
    b[i]=V[i-1].first+1;
  }
  for(int i=0;i<=n;i++)for(int k=0;k<=K;k++)D[i][k]=1e18;
  D[0][0]=0;
  for(int i=1;i<=n;i++)
  {
    for(int k=1;k<=i && k<=K;k++)
    {
      D[i][k]=1e18;
      for(int j=0;j<i;j++)
      {
        D[i][k]=min(D[i][k],D[j][k-1]+sq(b[i]-a[j+1]+1)-sq(b[j]-min(b[j],a[j+1]-1)));
      }
    }
  }
  lint ans=1e18;
  for(int k=1;k<=K;k++)ans=min(ans,D[n][k]);
  return ans;
}

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