Submission #617449

#	Time	Username	Problem	Language	Result	Execution time	Memory
617449		Hazem	Aliens (IOI16_aliens)	C++14	25 / 100	2074 ms	71648 KiB

aliens

#include <bits/stdc++.h>
#define F first
#define S second
#define LL long long

using namespace std;

const int N = 4e3+10;
const LL LINF = 1e18;

pair<int,int>p[N];
LL dp[N][N];

bool cmp(pair<int,int>p1,pair<int,int>p2){

    if(p1.F!=p2.F)
        return p1.F<p2.F;
    return p1.S>p2.S;
}

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++){
        if(r[i]>c[i])
            swap(r[i],c[i]);
        p[i] = {c[i],r[i]};
    }    

    sort(p,p+n);
    vector<pair<int,int>>vec;
    int mn = 1e9+10;
    for(int i=n-1;i>=0;i--){
        if(mn<=p[i].S)
            continue;
        vec.push_back(p[i]);
        mn = min(mn,p[i].S);
    }

    vec.push_back({-1,-1});
    reverse(vec.begin(),vec.end());

    for(int j=1;j<=k;j++)        
        dp[0][j] = LINF;
    
    for(int i=1;i<vec.size();i++){
        int last = 1;
        dp[i][0] = LINF;
        for(int j=1;j<=k;j++){
            dp[i][j] = LINF;
            if(last>1)
                last--;
            for(int j1 = last;j1<=i;j1++){
                LL d = (vec[i].F-vec[j1].S+1),d1 = max(0,vec[j1-1].F-vec[j1].S+1);
                d *= d;
                d1 *= d1;
                if(dp[j1-1][j-1]+d-d1<dp[i][j])
                    dp[i][j] = dp[j1-1][j-1]+d-d1,last = j1;
            }
        }
    }

    LL ans = LINF;
    for(int i=1;i<=k;i++)
        ans = min(ans,dp[vec.size()-1][i]);

    return ans;
}

Compilation message (stderr)

aliens.cpp: In function 'long long int take_photos(int, int, int, std::vector<int>, std::vector<int>)':
aliens.cpp:45:18: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<std::pair<int, int> >::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   45 |     for(int i=1;i<vec.size();i++){
      |                 ~^~~~~~~~~~~

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