Submission #1010987

#	Time	Username	Problem	Language	Result	Execution time	Memory
1010987		c2zi6	Aliens (IOI16_aliens)	C++14	4 / 100	1 ms	604 KiB

aliens

#define _USE_MATH_DEFINES
#include <bits/stdc++.h>
#define ff first
#define ss second
#define pb push_back
#define all(a) (a).begin(), (a).end()
#define replr(i, a, b) for (int i = int(a); i <= int(b); ++i)
#define reprl(i, a, b) for (int i = int(a); i >= int(b); --i)
#define rep(i, n) for (int i = 0; i < int(n); ++i)
#define mkp(a, b) make_pair(a, b)
using namespace std;
typedef long long ll;
typedef long double ld;
typedef pair<int, int> PII;
typedef vector<int> VI;
typedef vector<PII> VPI;
typedef vector<VI> VVI;
typedef vector<VVI> VVVI;
typedef vector<VPI> VVPI;
typedef pair<ll, ll> PLL;
typedef vector<ll> VL;
typedef vector<PLL> VPL;
typedef vector<VL> VVL;
typedef vector<VVL> VVVL;
typedef vector<VPL> VVPL;
template<class T> T setmax(T& a, T b) {if (a < b) return a = b; return a;}
template<class T> T setmin(T& a, T b) {if (a < b) return a; return a = b;}
#include <ext/pb_ds/assoc_container.hpp>
using namespace __gnu_pbds;
template<class T>
using indset = tree<T, null_type, less<T>, rb_tree_tag, tree_order_statistics_node_update>;
#include "aliens.h"

ll square(ll a) {
    return a*a;
}

ll take_photos(int n, int m, int k, VI R, VI C) {
    VPI pts;
    rep(i, n) {
        int r = R[i];
        int c = C[i];
        if (r > c) swap(r, c);
        pts.pb({r, c});
    }
    {
        VPI tmp;
        sort(all(pts));
        rep(i, n) {
            if (i == n-1 || pts[i+1].ff != pts[i].ff) {
                if (!tmp.size() || tmp.back().ss < pts[i].ss) {
                    tmp.pb(pts[i]);
                }
            }
        }
        pts = tmp;
        n = pts.size();
    }
    /*for (auto[r, c] : pts) cout << r << " " << c << endl;*/
    ll ans = 0;
    for (int i = 0; i < n; i++) {
        ans += square(pts[i].ss - pts[i].ff + 1);
        if (i) ans -= square(max(0, pts[i-1].ss - pts[i].ff + 1));
    }

    while (n > k) {
        int mini;
        ll minv = 1e18;
        rep(i, n-1) {
            ll diff = 0;
            diff += square(pts[i+1].ss - pts[i].ff + 1);
            diff -= square(pts[i+1].ss - pts[i+1].ff + 1);
            diff -= square(pts[i].ss - pts[i].ff + 1);
            diff += square(max(0, pts[i].ss - pts[i+1].ff + 1));
            if (diff < minv) {
                minv = diff;
                mini = i;
            }
        }
        ans += minv;
        VPI tmp;
        rep(i, n) {
            if (i == mini) {
                tmp.pb({pts[i].ff, pts[i+1].ss});
                i++;
            } else tmp.pb(pts[i]);
        }
        pts = tmp;
        n = pts.size();
        /*for (auto[r, c] : pts) cout << r << " " << c << endl;*/
        /*cout << endl;*/
    }

    return ans;
}

Compilation message (stderr)

aliens.cpp: In function 'll take_photos(int, int, int, VI, VI)':
aliens.cpp:83:13: warning: 'mini' may be used uninitialized in this function [-Wmaybe-uninitialized]
   83 |             if (i == mini) {
      |             ^~

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