Submission #773638

#	Time	Username	Problem	Language	Result	Execution time	Memory
773638		peteza	Aliens (IOI16_aliens)	C++14	12 / 100	47 ms	3220 KiB

aliens

#include "aliens.h"
#include <bits/stdc++.h>
using namespace std;
using pii = pair<int, int>;

long long dp[4005][4005];
long long square(long long x) {
    x = max(0ll, x);
    return x*x;
}

long long take_photos(int n, int m, int k, std::vector<int> r, std::vector<int> c) {
    std::vector<pii> points;
    std::vector<pii> rps;
    for(int i=0;i<n;i++) {
        if(r[i] < c[i]) points.emplace_back(r[i], c[i]);
        else points.emplace_back(c[i], r[i]);
    }
    sort(points.begin(), points.end(), [](pii a, pii b){return a.first < b.first || (a.first == b.first && a.second > b.second);});
    int last = -1;
    for(auto e:points) {
        if(last == e.first) continue;
        while(!rps.empty() && rps.back().second >= e.second) rps.pop_back();
        if(rps.empty() || rps.back().second < e.second) rps.emplace_back(e);
        last = e.first;
    }
    k = min(k, (int) rps.size());
    for(int i=0;i<rps.size();i++) dp[i][0] = square(rps[i].second-rps[0].first+1)/*, cout << dp[i][0] << ' '*/;
    for(int j=1;j<k;j++) {
        for(int i=j;i<rps.size();i++) {
            dp[i][j] = 1000000000000000000ll;
            for(int k=j-1;k<i;k++) {
                dp[i][j] = min(dp[i][j], dp[k][j-1] - square(rps[k].second-rps[k+1].first+1) + square(rps[i].second-rps[k+1].first+1));
                
            }
        }
    }
    return dp[rps.size()-1][k-1];
}
/*
#include <cstdio>
#include <cassert>

int main() {
    int n, m, k;
    assert(3 == scanf("%d %d %d", &n, &m, &k));
    std::vector<int> r(n), c(n);
    for (int i = 0; i < n; i++) {
        assert(2 == scanf("%d %d", &r[i], &c[i]));
    }
    long long ans = take_photos(n, m, k, r, c);
    
    
    printf("%lld\n", ans);
    return 0;
}
*/

Compilation message (stderr)

aliens.cpp: In function 'long long int take_photos(int, int, int, std::vector<int>, std::vector<int>)':
aliens.cpp:28:18: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<std::pair<int, int> >::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   28 |     for(int i=0;i<rps.size();i++) dp[i][0] = square(rps[i].second-rps[0].first+1)/*, cout << dp[i][0] << ' '*/;
      |                 ~^~~~~~~~~~~
aliens.cpp:30:22: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<std::pair<int, int> >::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   30 |         for(int i=j;i<rps.size();i++) {
      |                     ~^~~~~~~~~~~

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