house robber II solution

Author: hyer0705

house-robber-ii/hyer0705.ts

@@ -0,0 +1,26 @@
+// Time Complexity: O(n)
+// Space Complexity: O(1)
+function rob(nums: number[]): number {
+  const n = nums.length;
+
+  if (n === 1) return nums[0];
+  if (n === 2) return Math.max(nums[0], nums[1]);
+
+  const getLinearRob = (start: number, end: number) => {
+    let prev2 = 0;
+    let prev1 = 0;
+
+    for (let i = start; i <= end; i++) {
+      const current = Math.max(prev1, prev2 + nums[i]);
+      prev2 = prev1;
+      prev1 = current;
+    }
+
+    return prev1;
+  };
+
+  let case1 = getLinearRob(0, n - 2);
+  let case2 = getLinearRob(1, n - 1);
+
+  return Math.max(case1, case2);
+}