Create 1162-as-far-from-land-as-possible.js

Author: everthis

1162-as-far-from-land-as-possible.js

@@ -0,0 +1,31 @@
+/**
+ * @param {number[][]} grid
+ * @return {number}
+ */
+const maxDistance = function(grid) {
+  let m = grid.length
+  let n = m === 0 ? 0 : grid[0].length
+  let dp = new Array(m + 2)
+  for (let i = 0; i < m + 2; i++) {
+    dp[i] = new Array(n + 2).fill(Number.POSITIVE_INFINITY)
+  }
+  for (let i = 1; i <= m; i++) {
+    for (let j = 1; j <= n; j++) {
+      if (grid[i - 1][j - 1] === 0) {
+        dp[i][j] = Math.min(dp[i - 1][j], dp[i][j - 1]) + 1
+      } else {
+        dp[i][j] = 0
+      }
+    }
+  }
+  let res = Number.NEGATIVE_INFINITY
+  for (let i = m; i >= 1; i--) {
+    for (let j = n; j >= 1; j--) {
+      if (grid[i - 1][j - 1] === 0) {
+        dp[i][j] = Math.min(dp[i][j], Math.min(dp[i + 1][j], dp[i][j + 1]) + 1)
+        res = Math.max(res, dp[i][j])
+      }
+    }
+  }
+  return isFinite(res) ? res : -1
+}