제출 #1032916

#	제출 시각	아이디	문제	언어	결과	실행 시간	메모리
1032916		juicy	The Kingdom of JOIOI (JOI17_joioi)	C++17	100 / 100	718 ms	55020 KiB

joioi

#include <bits/stdc++.h>

using namespace std;

#ifdef LOCAL
#include "debug.h"
#else
#define debug(...) 42
#endif

const int N = 2e3 + 5, inf = 1e9;

int n, m, mn = inf, mx;
int a[N][N];

bool check(int k) {
	int cut = 0;
	for (int i = 1; i <= n; ++i) {
		for (int j = 1; j <= m; ++j) {
			if (a[i][j] < mx - k) {
				cut = max(cut, j);
			} 
		}
		for (int j = 1; j <= m; ++j) {
			if (a[i][j] > mn + k && cut >= j) {
				return 0;
			} 
		}
	}
	return 1;
}

int solve() {
	int L = 0, R = mx - mn, res = mx - mn;
	while (L <= R) {
		int md = (L + R) / 2;
		if (check(md)) {
			res = md;
			R = md - 1;
		} else {
			L = md + 1;
		}
	}
	return res;
}

void flip_row() {
	for (int j = 1; j <= m; ++j) {
		for (int i = 1; i <= n / 2; ++i) {
			swap(a[i][j], a[n - i + 1][j]);
		}
	}
}

void flip_col() {
	for (int i = 1; i <= n; ++i) {
		for (int j = 1; j <= m / 2; ++j) {
			swap(a[i][j], a[i][m - j + 1]);
		}
	}
}

int main() {
	ios::sync_with_stdio(false); cin.tie(nullptr);

	cin >> n >> m;
	for (int i = 1; i <= n; ++i) {
		for (int j = 1; j <= m; ++j) {
			cin >> a[i][j];
			mn = min(mn, a[i][j]);
			mx = max(mx, a[i][j]);
		}
	}	
	int res = solve();
	flip_row();
	res = min(res, solve());
	flip_col();
	res = min(res, solve());
	flip_row();
	res = min(res, solve());
	cout << res;
	return 0;
}

• Subtask 1: 15 / 15
• Subtask 2: 45 / 45
• Subtask 3: 40 / 40