Create 1915.cpp

Author: encrypted-def

Appendix E/1915.cpp

@@ -0,0 +1,37 @@
+#include <bits/stdc++.h>
+using namespace std;
+
+int n, m;
+string board[1005];
+int d[1005][1005];
+
+int main(void) {
+  ios::sync_with_stdio(0);
+  cin.tie(0);
+
+  cin >> n >> m;
+  for(int i = 0; i < n; i++)
+    cin >> board[i];
+
+  for(int i = 0; i < n; i++)
+    d[i][0] = board[i][0] - '0';
+
+  for(int j = 0; j < m; j++)
+    d[0][j] = board[0][j] - '0';
+
+  for(int i = 1; i < n; i++){
+    for(int j = 1; j < m; j++){
+      if(board[i][j] == '0')
+        continue;
+      d[i][j] = min({d[i-1][j], d[i-1][j-1], d[i][j-1]}) + 1;
+    }
+  }
+
+  int ans = 0;
+  for(int i = 0; i < n; i++){
+    for(int j = 0; j < m; j++)
+      ans = max(ans, d[i][j]);
+  }
+
+  cout << ans * ans << '\n'; 
+}