Create 198_House_Robber

Author: srishilesh

Leet Code/Practice/198_House_Robber

@@ -0,0 +1,63 @@
+// https://leetcode.com/problems/house-robber/
+
+// ITERATIVE WITH TWO VARIABLES
+class Solution {
+    public int rob(int[] nums) {
+        if (nums.length == 0) return 0;
+        int prev1 = 0;
+        int prev2 = 0;
+        for (int num : nums) {
+            int tmp = prev1;
+            prev1 = Math.max(prev1, prev2 + num);
+            prev2 = tmp;
+        }
+        return prev1;
+    }
+}
+
+// ITERATIVE WITH MEMOIZATION - BOTTOM UP APPROACH
+// class Solution {
+//     public int rob(int []nums) {
+//         if (nums.length == 0)   
+//             return 0;
+//         int[] memo = new int[nums.length + 1];
+//         memo[0] = 0;
+//         memo[1] = nums[0];
+//         for (int i = 1; i < nums.length; i++) {
+//             int val = nums[i];
+//             memo[i+1] = Math.max(memo[i], memo[i - 1] + val);
+//         }
+//         return memo[nums.length];
+//     }
+// }
+
+// RECURSIVE WITH MEMOIZATION - TOP DOWN APPROACH
+// class Solution {
+//     int[] memo;
+//     public int rob(int[] nums) {
+//         memo = new int[nums.length + 1];
+//         Arrays.fill(memo, -1);
+//         return rob(nums, nums.length - 1);
+//     }
+//     public int rob(int[] nums, int i) {
+//         if (i < 0)
+//             return 0;
+//         if (memo[i] >= 0)
+//             return memo[i];
+//         memo[i] = Math.max(rob(nums, i - 2) + nums[i], rob(nums, i - 1));
+//         return memo[i];
+//     }
+// }
+
+// RECURSIVE - TOP DOWN APPROACH
+// class Solution {
+//     public int rob(int[] nums) {
+//         return rob(nums, nums.length - 1);
+//     }
+//     public int rob(int[] nums, int i) {
+//         if (i < 0)
+//             return 0;
+//         return Math.max(rob(nums, i-2) + nums[i], rob(nums, i-1));
+            
+//     }
+// }