add: 最大正方形

src/array/maximal-square.js

@@ -0,0 +1,25 @@
+/**
+ * @param {character[][]} matrix
+ * @return {number}
+ */
+export const maximalSquare = function (matrix) {
+  if (!matrix || !matrix[0]) return 0
+
+  const rows = matrix.length
+  const cols = matrix[0].length
+  let max = 0
+
+  const dp = new Array(rows).fill().map(_ => new Array(cols).fill(0))
+
+  for (let n = 0; n < rows; n++) {
+    for (let i = 0; i < cols; i++) {
+      if (Number(matrix[n][i]) === 1) {
+        if (n === 0 || i === 0) dp[n][i] = 1
+        else dp[n][i] = Math.min(dp[n - 1][i], dp[n][i - 1], dp[n - 1][i - 1]) + 1 // 找规律
+        max = Math.max(max, dp[n][i])
+      }
+    }
+  }
+
+  return max * max
+}