Submission #561210

#	Time	Username	Problem	Language	Result	Execution time	Memory
561210		flappybird	The Kingdom of JOIOI (JOI17_joioi)	C++17	100 / 100	746 ms	55620 KiB

joioi

#include <bits/stdc++.h>
#include <cassert>
#pragma GCC optimize("O3")
#pragma GCC optimize("Ofast")
#pragma GCC optimize("unroll-loops")
#pragma GCC target("avx,avx2,fma")
using namespace std;
typedef long long ll;
typedef pair<ll, ll> pll;
typedef pair<int, int> pii;
#define MAX 2100
#define MAXS 20
#define INF 1000000000000000001
#define bb ' '
#define ln '\n'
#define Ln '\n'
int arr[MAX][MAX];
pii range[MAX];
int N, M;
bool rchk() {
	int i;
	int mnn = -1;
	bool cc = true;
	for (i = 1; i <= N; i++) {
		if (mnn < range[i].first) mnn = range[i].first;
		else {
			if (mnn >= range[i].second) {
				cc = false;
				break;
			}
		}
	}
	if (cc) return true;
	cc = true;
	mnn = -1;
	for (i = N; i >= 1; i--) {
		if (mnn < range[i].first) mnn = range[i].first;
		else {
			if (mnn >= range[i].second) {
				cc = false;
				break;
			}
		}
	}
	return cc;
}
signed main() {
	ios::sync_with_stdio(false), cin.tie(0);
	cin >> N >> M;
	int i, j;
	int mn = 1000000010;
	int mx = 0;
	for (i = 1; i <= N; i++) {
		for (j = 1; j <= M; j++) {
			cin >> arr[i][j];
			mx = max(arr[i][j], mx);
			mn = min(arr[i][j], mn);
		}
	}
	if (mx == mn) {
		cout << 0 << ln;
		return 0;
	}
	int l, r;
	l = -1;
	r = mx - mn;
	int mid;
	while (r - l > 1) {
		mid = (l + r + 1) / 2;
		bool chk = true;
		for (i = 1; i <= N; i++) {
			range[i] = { 0, M + 1 };
			for (j = 1; j <= M; j++) if (mx - arr[i][j] > mid) range[i].first = j;
			for (j = M; j >= 1; j--) if (arr[i][j] - mn > mid) range[i].second = j;
			if (range[i].first >= range[i].second) {
				chk = false;
				break;
			}
		}
		if (chk) chk = rchk();
		if (!chk) {
			chk = true;
			for (i = 1; i <= N; i++) {
				range[i] = { 0, M + 1 };
				for (j = 1; j <= M; j++) if (arr[i][j] - mn > mid) range[i].first = j;
				for (j = M; j >= 1; j--) if (mx - arr[i][j] > mid) range[i].second = j;
				if (range[i].first >= range[i].second) {
					chk = false;
					break;
				}
			}
			if (chk) chk = rchk();
		}
		if (chk) r = mid;
		else l = mid;
	}
	cout << r << ln;
}

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