Submission #139746

#	Time	Username	Problem	Language	Result	Execution time	Memory
139746		BThero	Aliens (IOI16_aliens)	C++17	25 / 100	2052 ms	16888 KiB

aliens

// Why am I so dumb? :c
// chrono::system_clock::now().time_since_epoch().count()

//#pragma GCC optimize("Ofast")
//#pragma GCC target("sse,sse2,sse3,ssse3,sse4,popcnt,abm,mmx,avx,tune=native")

#include <bits/stdc++.h>
#include <ext/pb_ds/assoc_container.hpp>
#include <ext/pb_ds/tree_policy.hpp>
#include "aliens.h"

#define pb push_back
#define mp make_pair

#define all(x) (x).begin(), (x).end()
#define debug(x) cerr << #x << " = " << x << '\n';

#define fi first
#define se second

using namespace std;
using namespace __gnu_pbds;

typedef long long ll;   
typedef pair<int, int> pii;
template<typename T> using ordered_set = tree<T, null_type, less<T>, rb_tree_tag, tree_order_statistics_node_update>;

const int MAXN = (int)4e3 + 5;
const int INF = (int)1e9;
const ll LINF = (ll)1e15;

ll dp[MAXN][MAXN];

pii arr[MAXN];

int n, m, k;

bool cmp(pii a, pii b) {
    if (a.fi == b.fi) {
        return a.se > b.se;
    }
    
    return a.fi < b.fi;
}

void resolveOverlaps() {
    sort(arr + 1, arr + n + 1, cmp);
    int lim = 0, nn = 0;
    
    for (int i = 1; i <= n; ++i) {
        if (arr[i].se > lim) {
            arr[++nn] = arr[i];
            lim = arr[i].se;
        }
    }
    
    n = nn;
}

ll f(int a, int b) {
    int len = max(0, b - a + 1);
    return len * 1ll * len;
}

ll solve() {
    for (int i = 1; i <= n; ++i) {
        if (arr[i].fi > arr[i].se) {
            swap(arr[i].fi, arr[i].se);
        }
    }
    
    resolveOverlaps();
    
    for (int i = 1; i <= n; ++i) {
        for (int j = 0; j <= k; ++j) {
            dp[i][j] = LINF;
        }
    }
    
    for (int i = 1; i <= n; ++i) {
        for (int t = 1; t <= k; ++t) {
            for (int j = 1; j <= i; ++j) {
                dp[i][t] = min(dp[i][t], dp[j - 1][t - 1] + f(arr[j].fi, arr[i].se) - f(arr[j].fi, arr[j - 1].se));
            }
        }
    }
    
    return dp[n][k];
}

ll take_photos(int _n, int _m, int _k, vector<int> r, vector<int> c) {
    n = _n;
    m = _m;
    k = _k;
    
    for (int i = 1; i <= n; ++i) {
        arr[i] = mp(r[i - 1] + 1, c[i - 1] + 1);
    }

    return solve();
}

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