Feat: 213. House Robber II

Author: HC-kang

house-robber-ii/HC-kang.ts

@@ -0,0 +1,26 @@
+/**
+ * https://leetcode.com/problems/house-robber-ii
+ * T.C. O(n)
+ * S.C. O(1)
+ */
+function rob(nums: number[]): number {
+  if (nums.length === 1) return nums[0];
+  if (nums.length === 2) return Math.max(nums[0], nums[1]);
+  if (nums.length === 3) return Math.max(nums[0], nums[1], nums[2]);
+
+  function robHelper(nums: number[]): number {
+    let prev = 0;
+    let curr = 0;
+    for (let i = 0; i < nums.length; i++) {
+      const temp = curr;
+      curr = Math.max(prev + nums[i], curr);
+      prev = temp;
+    }
+    return curr;
+  }
+
+  const robFirst = robHelper(nums.slice(0, nums.length - 1));
+  const robLast = robHelper(nums.slice(1));
+
+  return Math.max(robFirst, robLast);
+}