Submission #425763

#	Time	Username	Problem	Language	Result	Execution time	Memory
425763		ngrace	Aliens (IOI16_aliens)	C++14	4 / 100	2140 ms	994424 KiB

aliens

#include "aliens.h"
#include <vector>
#include <iostream>
#include <utility>
#include <algorithm>
#include <set>
using namespace std;
#define v vector
#define pii pair<int,int>
#define fi first
#define se second
 
int N,K;
v<int> pos;
v<v<v<long long>>> memo;
long long diagSolve(int l, int r, int k){
    long long curArea=(pos[r]-pos[l]+1) * (pos[r]-pos[l]+1);
    if(r==N-1){
        return memo[l][r][k] = curArea;
    }
    if(k==K-1){
        return memo[l][r][k] = (pos.back()-pos[l]+1) * (pos.back()-pos[l]+1);
    }
    if(memo[l][r][k]!=-1) return memo[l][r][k];
 
    long long takePhoto = curArea+diagSolve(r+1,r+1,k+1);
    long long dont = diagSolve(l,r+1,k);
    return memo[l][r][k] = min(takePhoto, dont);
}
 
 
 
long long take_photos(int n, int m, int k, std::vector<int> r, std::vector<int> c) {
    bool subTwo=true;
    for(int i=0;i<n;i++){
        if(r[i]!=c[i]) subTwo=false;
    }
    
    if(k==n && m<=100){//sub 1
        v<v<bool>> squares(m,v<bool>(m,false));
        for(int i=0;i<n;i++){
            int low=min(r[i],c[i]);
            int high=max(r[i],c[i]);
            for(int a=low;a<=high;a++){
                for(int b=low;b<=high;b++){
                    squares[a][b]=true;
                }
            }
        }
 
        long long out=0;
        for(int i=0;i<m;i++){
            for(int j=0;j<m;j++){
                out+=squares[i][j];
            }
        }
        return out;
    }
    else if(subTwo){//assume sub 2
        //as all along diagonal can do dp with n^3
        K=k;
        N=n;
        set<int> tmp;
        for(int i:r) tmp.insert(i);
        for(int i:tmp) pos.push_back(i);
        N=pos.size();
        memo=v<v<v<long long>>>(pos.size()+1,v<v<long long>>(pos.size()+1,v<long long>(k+1,-1)));
        return diagSolve(0,0,0);
    }
}

Compilation message (stderr)

aliens.cpp: In function 'long long int take_photos(int, int, int, std::vector<int>, std::vector<int>)':
aliens.cpp:70:1: warning: control reaches end of non-void function [-Wreturn-type]
   70 | }
      | ^

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