Time: 1 ms (65.17%), Space: 55.9 MB (5.67%) - LeetHub

Author: chappdev2019

0289-game-of-life/0289-game-of-life.js

@@ -0,0 +1,35 @@
+/**
+ * @param {number[][]} board
+ * @return {void} Do not return anything, modify board in-place instead.
+ */
+var gameOfLife = function (board) {
+
+    let dirs = [[1, 0], [-1, 0], [0, 1], [0, -1], [-1, -1], [1, 1], [1, -1], [-1, 1]];
+    const calNeighborCount = (i, j) => {
+        let count = 0;
+        for (const [r, c] of dirs) {
+            let newR = i + r;
+            let newC = j + c;
+            if (newR < 0 || newC < 0 || newR >= board.length || newC >= board[0].length) continue;
+            if (board[newR][newC] === 1 || board[newR][newC] === -1) count++;
+        }
+        return count;
+    }
+    for (let i = 0; i < board.length; i++) {
+        for (let j = 0; j < board[0].length; j++) {
+            let liveNeighbors = calNeighborCount(i, j);
+            if (board[i][j] == 1) {
+                if (liveNeighbors == 2 || liveNeighbors == 3) continue;
+                board[i][j] = -1;
+            } else {
+                if (liveNeighbors == 3) board[i][j] = 2;
+            }
+        }
+    }
+    for (let i = 0; i < board.length; i++) {
+        for (let j = 0; j < board[0].length; j++) {
+            if (board[i][j] === -1) board[i][j] = 0; 
+            if (board[i][j] === 2) board[i][j] = 1; 
+        }
+    }
+};