Submission #674180

#	Time	Username	Problem	Language	Result	Execution time	Memory
674180		QwertyPi	Maxcomp (info1cup18_maxcomp)	C++14	100 / 100	384 ms	45220 KiB

maxcomp

#include <bits/stdc++.h>
#define int long long
#define fi first
#define se second
#define pii pair<int, int>
using namespace std;

const int MOD = 1e9 + 7;
const int MAXN = 1e5 + 11;
const int B = 800;

int a[1001][1001];
int mx[1001][1001];
bool vis[1001][1001];

int dx[4] = {1, -1, 0, 0}, dy[4] = {0, 0, 1, -1};

int n, m; 
bool in(int i, int j){
	return 0 <= i && i < n && 0 <= j && j < m;
}

vector<pair<int, int>> dq[2001];
int32_t main(){
	cin >> n >> m;
	for(int i = 0; i < n; i++){
		for(int j = 0; j < m; j++){
			cin >> a[i][j];
			mx[i][j] = a[i][j];
		}
	}

	int _mx = 0;
	for(int i = 0; i < n; i++){
		for(int j = 0; j < m; j++){
			_mx = max(_mx, a[i][j]);
		}
	}
	
	for(int i = 0; i < n; i++){
		for(int j = 0; j < m; j++){
			if(mx[i][j] >= _mx - n - m) dq[n + m + mx[i][j] - _mx].push_back({mx[i][j], i * m + j});
		}
	}
	for(int k = n + m; k >= 0; k--){
		for(auto t : dq[k]){
			int i = t.se / m, j = t.se % m, val = t.fi;
			if(mx[i][j] != val || vis[i][j]) continue; vis[i][j] = true;
			for(int dir = 0; dir < 4; dir++){
				if(in(i + dx[dir], j + dy[dir]) && mx[i + dx[dir]][j + dy[dir]] < mx[i][j] - 1){
					mx[i + dx[dir]][j + dy[dir]] = mx[i][j] - 1;
					int ni = i + dx[dir], nj = j + dy[dir];
					dq[n + m + mx[i + dx[dir]][j + dy[dir]] - _mx].push_back({mx[i + dx[dir]][j + dy[dir]], ni * m + nj});
				}
			}
		}
	}
	
	int ans = -1;
	for(int i = 0; i < n; i++){
		for(int j = 0; j < m; j++){
			ans = max(ans, mx[i][j] - a[i][j] - 1);
		}
	}
	cout << ans << endl;
}

Compilation message (stderr)

maxcomp.cpp: In function 'int32_t main()':
maxcomp.cpp:48:4: warning: this 'if' clause does not guard... [-Wmisleading-indentation]
   48 |    if(mx[i][j] != val || vis[i][j]) continue; vis[i][j] = true;
      |    ^~
maxcomp.cpp:48:47: note: ...this statement, but the latter is misleadingly indented as if it were guarded by the 'if'
   48 |    if(mx[i][j] != val || vis[i][j]) continue; vis[i][j] = true;
      |                                               ^~~

• Subtask 1: 15 / 15
• Subtask 2: 15 / 15
• Subtask 3: 30 / 30
• Subtask 4: 40 / 40