Create 542-01-matrix.js

Author: everthis

542-01-matrix.js

@@ -0,0 +1,48 @@
+/**
+ * @param {number[][]} matrix
+ * @return {number[][]}
+ */
+
+const updateMatrix = function (matrix) {
+    const rows = matrix.length, cols = matrix[0].length;
+    const maxDist = rows + cols;
+    let dist = new Array(rows).fill(null).map(() => new Array(cols).fill(0));
+  
+    for (let i = 0; i < rows; i++) {
+      for (let j = 0; j < cols; j++) {
+        if (matrix[i][j] !== 0) {
+          dist[i][j] = hasNeighborZero(i, j, matrix, rows, cols) ? 1 : maxDist;
+        }
+      }
+    }
+  
+    for (let i = 0; i < rows; i++) {
+      for (let j = 0; j < cols; j++) {
+        if (dist[i][j] === 1) {
+          dfs(dist, i, j, -1);
+        }
+      }
+    }
+  
+    return dist;
+  };
+  
+  const dfs = function (dist, row, col, step) {
+    if (row < 0 || row >= dist.length || col < 0 || col >= dist[0].length || dist[row][col] <= step) return;
+  
+    if (step > 0) dist[row][col] = step;
+  
+    dfs(dist, row + 1, col, dist[row][col] + 1);
+    dfs(dist, row - 1, col, dist[row][col] + 1);
+    dfs(dist, row, col + 1, dist[row][col] + 1);
+    dfs(dist, row, col - 1, dist[row][col] + 1);
+  };
+  
+  const hasNeighborZero = function (row, col, matrix, rows, cols) {
+    if (row < rows - 1 && matrix[row + 1][col] === 0) return true;
+    if (row > 0 && matrix[row - 1][col] === 0) return true;
+    if (col > 0 && matrix[row][col - 1] === 0) return true;
+    if (col < cols - 1 && matrix[row][col + 1] === 0) return true;
+  
+    return false;
+  };