Submission #666839

#	Time	Username	Problem	Language	Result	Execution time	Memory
666839		Lobo	Aliens (IOI16_aliens)	C++17	25 / 100	2079 ms	6892 KiB

aliens

#include<bits/stdc++.h>
#include "aliens.h"
using namespace std;
#define int long long
#define fr first
#define sc second
#define mp make_pair
#define pb push_back
#define all(x) x.begin(),x.end()
const int inf = 1e18+10;
int n;
vector<pair<int,int>> pts;

int sol(int K) {
    int dp[n][K+1];
    for(int i = 0; i < n; i++) dp[i][0] = inf;

    for(int k = 1; k <= K; k++) {
        for(int i = 0; i < n; i++) {
            dp[i][k] = inf;
            int xi = pts[i].fr;
            int yi = pts[i].sc;
            for(int j = 0; j <= i; j++) {
                int xj = pts[j].fr;
                int yj = pts[j].sc;
                if(j == 0) {
                    dp[i][k] = min(dp[i][k], (xi*xi + 2*xi + 1) + (yj*yj - 2*yj)  + (- 2*xi*yj));
                }
                else {
                    int xj1 = pts[j-1].fr;
                    int yj1 = pts[j-1].sc;
                    dp[i][k] = min(dp[i][k] ,(xi*xi + 2*xi + 1) + (dp[j-1][k-1] + yj*yj - 2*yj - max((int)0,xj1-yj+1)*max((int) 0,xj1-yj+1))  + (- 2*xi*yj));
                }
            }
        }
    }
    return dp[n-1][K];
}

int take_photos(int32_t N, int32_t m, int32_t k, vector<int32_t> r, vector<int32_t> c) {
    for(int i = 0; i < N; i++) {
        int x = c[i];
        int y = r[i];
        if(x < y) swap(x,y);
        pts.pb(mp(x,-y));
    }

    sort(all(pts));

    stack<pair<int,int>> prt;
    for(auto X : pts) {
        int x = X.fr;
        int y = -X.sc;

        while(prt.size() && prt.top().sc >= y) prt.pop();
        prt.push(mp(x,y));
    }
    pts.clear();
    while(prt.size()) {
        pts.pb(prt.top());
        prt.pop();
    }
    sort(all(pts));
    n = pts.size();

    return sol(k);
}

Compilation message (stderr)

aliens.cpp: In function 'long long int sol(long long int)':
aliens.cpp:31:25: warning: unused variable 'yj1' [-Wunused-variable]
   31 |                     int yj1 = pts[j-1].sc;
      |                         ^~~
aliens.cpp:24:21: warning: unused variable 'xj' [-Wunused-variable]
   24 |                 int xj = pts[j].fr;
      |                     ^~
aliens.cpp:22:17: warning: unused variable 'yi' [-Wunused-variable]
   22 |             int yi = pts[i].sc;
      |                 ^~

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