Submission #687569

#	Time	Username	Problem	Language	Result	Execution time	Memory
687569		NK_	The Kingdom of JOIOI (JOI17_joioi)	C++17	100 / 100	2009 ms	119232 KiB

joioi

// Success consists of going from failure to failure without loss of enthusiasm
#include <bits/stdc++.h>

using namespace std;

#define nl '\n'

int main() {
	cin.tie(0)->sync_with_stdio(0);
	
	int N, M; cin >> N >> M;
	vector<vector<int>> A(N, vector<int>(M)); for(auto& v : A) for(auto& x : v) cin >> x;

	vector<int> U; 
	vector<array<int, 3>> I;
	for(int i = 0; i < N; i++) for(int j = 0; j < M; j++) {
		U.push_back(A[i][j]);
		I.push_back({A[i][j], i, j});
	}

	sort(rbegin(I), rend(I));
	sort(begin(U), end(U));
	U.erase(unique(begin(U), end(U)), end(U));

	auto solve = [&]() {
		vector<vector<int>> P(N, vector<int>(M));
		vector<int> JOI;
		for(auto i : I) P[i[1]][i[2]] = i[0];

		for(int i = 0; i < N; i++) for(int j = 0; j < M; j++) {
			if (i != 0) P[i][j] = min(P[i][j], P[i-1][j]);
			if (j != 0) P[i][j] = min(P[i][j], P[i][j-1]);
		}

		JOI = U;

		int ans = int(1e9);
		int mn = ans, mx = -ans;
		for(int i = 0; i < int(size(I)); i++) {
			int j = i;
			while(j < int(size(I)) && I[i][0] == I[j][0]) {
				int r = I[j][1], c = I[j][2];
				mn = min(mn, P[r][c]);
				j++;
			}
			mx = max(mx, I[i][0]);
			JOI.pop_back();

			if (size(JOI) == 0) break;

			// cout << I[i][0] << endl;

			// for(auto x : JOI) cout << x << " ";
			// cout << endl;

			// for(auto x : IOI) cout << x << " ";
			// cout << endl;

			int res = max(JOI.back() - JOI.front(), mx - mn);
			// cout << range(JOI) << " " << range(IOI) << endl;
			ans = min(ans, res);
			i = j-1;
		}

		return ans;
	};

	int ans = int(1e9);
	for(int f1 = 0; f1 < 2; f1++) {
		for(int f2 = 0; f2 < 2; f2++) {
			// cout << 2 * f1 + f2 << nl;
			ans = min(ans, solve());

			for(auto &i : I) i[2] = M - 1 - i[2];
		}

		for(auto &i : I) i[1] = N - 1 - i[1];
	}

	cout << ans << nl;



    return 0;
}

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