Submission #743827

#	Time	Username	Problem	Language	Result	Execution time	Memory
743827		baojiaopisu	Aliens (IOI16_aliens)	C++14	25 / 100	119 ms	8912 KiB

aliens

#include "aliens.h"
#include<bits/stdc++.h>

using namespace std;

using ll = long long;
using ld = long double;
using ull = unsigned long long;

using pii = pair<int, int>;
using pll = pair<ll, ll>;
using pld = pair<ld, ld>;

#define fi first
#define se second
#define left BAO
#define right ANH
#define pb push_back
#define pf push_front
#define mp make_pair
#define ins insert
#define btpc __builtin_popcount
#define btclz __builtin_clz

#define sz(x) (int)(x.size());
#define all(x) x.begin(), x.end()
#define debug(...) " [" << #__VA_ARGS__ ": " << (__VA_ARGS__) << "] "

mt19937 rng(chrono::steady_clock::now().time_since_epoch().count());

int d4x[4] = {1, 0, -1, 0}; int d4y[4] = {0, 1, 0, -1};
int d8x[8] = {0, 1, 1, 1, 0, -1, -1, -1};
int d8y[8] = {1, 1, 0, -1, -1, -1, 0, 1};

template<class X, class Y>
    bool minimize(X &x, const Y &y) {
        if (x > y)
        {
            x = y;
            return true;
        }
        return false;
    }
template<class X, class Y>
    bool maximize(X &x, const Y &y) {
        if (x < y)
        {
            x = y;
            return true;
        }
        return false;
    }

const int MOD = 1e9 + 7; //998244353

template<class X, class Y>
	void add(X &x, const Y &y) {
		x = (x + y);
		if(x >= MOD) x -= MOD;
	}

template<class X, class Y> 
	void sub(X &x, const Y &y) {
		x = (x - y);
		if(x < 0) x += MOD;
	}

/* Author : Le Ngoc Bao Anh, 12A5, LQD High School for Gifted Student*/

const ll INF = 1e18;
const ll LIM = 1e14;
const int N = 1e6 + 10;

ll dp[505][505];
int Lopt[505][505], Ropt[505][505];
ll g[N];

ll take_photos(int n, int m, int k, vector<int> x, vector<int> y) {
	vector<pii> point, npoint;
	for(int i = 0; i < m; i++) g[i] = INF;

	for(int i = 0; i < n; i++) {
		if(y[i] > x[i]) swap(x[i], y[i]);
		minimize(g[x[i]], y[i]);
	}

	for(int i = 0; i < m; i++) if(g[i] <= m) point.pb({i, g[i]}); 

	sort(all(point));

	ll D = INF;
	for(int i = point.size() - 1; i >= 0; i--) {
		if(point[i].se >= D) continue;
		npoint.pb(point[i]);
		D = point[i].se;
	}

	point = npoint;
	sort(all(point));
	for(int i = 0; i <= point.size(); i++) {
		for(int j = 0; j <= k; j++) dp[i][j] = INF, Lopt[i][j] = Ropt[i][j] = -1;
	}
	
	ll ans = INF;
	for(int i = 0; i < point.size(); i++) {
		if(i == 0) {
			ll d = (point[i].fi - point[i].se + 1);
			dp[i][1] = d * d;
			if(i == point.size() - 1) minimize(ans, d * d);
			continue;
		}	

		for(int j = 1; j <= min(k, i + 1); j++) {
			for(int t = i; t >= 0; t--) {
				ll d = point[i].fi - point[i].se + 1 + point[i].se - point[t].se;
				ll cost = d * d;
				if(t > 0) {
					if(point[t - 1].fi >= point[t].se) {
						ll d = point[t - 1].fi - point[t].se + 1;
						cost -= d * d;
					} 
					cost += dp[t - 1][j - 1];
				} 
				if(minimize(dp[i][j], cost)) {
					if(Ropt[i][j] == -1) Ropt[i][j] = t;
					Lopt[i][j] = t;
				}
				if(i == point.size() - 1) minimize(ans, cost);
			}
		}
	}

	for(int i = 0; i < point.size(); i++) {
		for(int j = 0; j < k; j++) {
			if(dp[i][j] >= LIM || dp[i][j + 1] >= LIM) continue;
			assert(Lopt[i][j] <= Ropt[i][j + 1]);
		}

		for(int j = 0; j <= k; j++) {
			if(i == 0 || dp[i][j] >= LIM || dp[i - 1][j] >= LIM) continue;
			assert(Lopt[i - 1][j] <= Ropt[i][j]);
		}
	}

	return ans;
}

Compilation message (stderr)

aliens.cpp: In function 'll take_photos(int, int, int, std::vector<int>, std::vector<int>)':
aliens.cpp:100:19: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<std::pair<int, int> >::size_type' {aka 'long unsigned int'} [-Wsign-compare]
  100 |  for(int i = 0; i <= point.size(); i++) {
      |                 ~~^~~~~~~~~~~~~~~
aliens.cpp:105:19: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<std::pair<int, int> >::size_type' {aka 'long unsigned int'} [-Wsign-compare]
  105 |  for(int i = 0; i < point.size(); i++) {
      |                 ~~^~~~~~~~~~~~~~
aliens.cpp:109:9: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<std::pair<int, int> >::size_type' {aka 'long unsigned int'} [-Wsign-compare]
  109 |    if(i == point.size() - 1) minimize(ans, d * d);
      |       ~~^~~~~~~~~~~~~~~~~~~
aliens.cpp:128:10: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<std::pair<int, int> >::size_type' {aka 'long unsigned int'} [-Wsign-compare]
  128 |     if(i == point.size() - 1) minimize(ans, cost);
      |        ~~^~~~~~~~~~~~~~~~~~~
aliens.cpp:133:19: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<std::pair<int, int> >::size_type' {aka 'long unsigned int'} [-Wsign-compare]
  133 |  for(int i = 0; i < point.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