From 2a237fe670739b46eeac2a051fa8b5a4504e340f Mon Sep 17 00:00:00 2001
From: Joshua Yoon <joshyoon92@gmail.com>
Date: Mon, 18 Oct 2021 17:02:15 -0500
Subject: [PATCH 1/3] Completed DP1

---
 CoinChange.java  | 24 ++++++++++++++++++++++++
 HoseRobber2.java | 20 ++++++++++++++++++++
 HouseRobber.java | 15 +++++++++++++++
 3 files changed, 59 insertions(+)
 create mode 100644 CoinChange.java
 create mode 100644 HoseRobber2.java
 create mode 100644 HouseRobber.java

diff --git a/CoinChange.java b/CoinChange.java
new file mode 100644
index 00000000..bfc46619
--- /dev/null
+++ b/CoinChange.java
@@ -0,0 +1,24 @@
+class CoinChange {
+    public int coinChange(int[] coins, int amount) {
+        int[][] dp = new int[coins.length + 1][amount + 1];
+
+        for (int i = 1; i <= amount; i++) {
+            dp[0][i] = amount + 1;
+        }
+        for (int i = 1; i <= coins.length; i++) {
+            dp[i][0] = 0;
+        }
+        for (int row = 1; row <= coins.length; row++) {
+            for (int col = 1; col <= amount; col++) {
+                if (col < coins[row - 1]) {
+                    dp[row][col] = dp[row - 1][col];
+                } else {
+                    dp[row][col] = Math.min(dp[row - 1][col], dp[row][col - coins[row - 1]] + 1);
+                }
+            }
+        }
+        return dp[coins.length][amount] == amount + 1 ? -1 : dp[coins.length][amount];
+    }
+}
+
+// Time Complexity: n x m, Space: n x m
\ No newline at end of file
diff --git a/HoseRobber2.java b/HoseRobber2.java
new file mode 100644
index 00000000..d50774e6
--- /dev/null
+++ b/HoseRobber2.java
@@ -0,0 +1,20 @@
+public class HoseRobber2 {
+    public int robber(int[] nums) {
+        int[][] dp = new int[nums.length + 1][2];
+        dp[0][1] = 0;
+        dp[1][0] = 0;
+        int max = Integer.MIN_VALUE;
+
+        for (int row = 1; row <= nums.length; row++) {
+            int notTaken = Math.max(dp[row - 1][0], dp[row - 1][1]);
+            int taken = dp[row - 1][0] + nums[row - 1];
+            max = Math.max(max, Math.max(notTaken, taken));
+
+            dp[row][0] = notTaken;
+            dp[row][1] = taken;
+        }
+
+        return max;
+
+    }
+}
diff --git a/HouseRobber.java b/HouseRobber.java
new file mode 100644
index 00000000..22383bf5
--- /dev/null
+++ b/HouseRobber.java
@@ -0,0 +1,15 @@
+public class HouseRobber {
+    public int rob(int[] nums) {
+        return helper(nums, 0);
+    }
+
+    public int helper(int[] nums, int index) {
+        if (index >= nums.length) {
+            return 0;
+        }
+        int robbed = nums[index] + helper(nums, index + 2);
+        int notRobbed = helper(nums, index + 1);
+        return Math.max(robbed, notRobbed);
+    }
+
+}

From f6d6c5b479c10032b93504335ec3cd3b11c5a164 Mon Sep 17 00:00:00 2001
From: Joshua Yoon <joshyoon92@gmail.com>
Date: Mon, 15 Jun 2026 17:54:47 -0500
Subject: [PATCH 2/3] dp-1 commit

---
 CoinChange.java  | 25 ++++++++++++++++++++++
 HouseRobber.java | 54 ++++++++++++++++++++++++++++++++++++++++++++++++
 2 files changed, 79 insertions(+)
 create mode 100644 CoinChange.java
 create mode 100644 HouseRobber.java

diff --git a/CoinChange.java b/CoinChange.java
new file mode 100644
index 00000000..34ea419f
--- /dev/null
+++ b/CoinChange.java
@@ -0,0 +1,25 @@
+public class CoinChange<T> {
+    public int coinChange(int[] coins, int amount) {
+        int col = amount;
+        int[] dp = new int[col+1];
+        for (int i=1; i<col+1; i++){
+            dp[i] = amount+1;
+        }
+        for (int i=1; i<coins.length+1; i++){
+            for (int j=1; j<col+1; j++){
+                // if denomination > amount -> num from above
+                if (coins[i-1] > j){
+                    dp[j] = dp[j];
+                } 
+                // get min of above and i-denomnination +1
+                else{
+                    dp[j] = Math.min(dp[j],1+ dp[j-coins[i-1]]);
+                }
+            }
+        }
+        int ans = dp[col];
+        if (ans > amount) return -1;
+        return ans;
+    }
+
+}
diff --git a/HouseRobber.java b/HouseRobber.java
new file mode 100644
index 00000000..b6ce878d
--- /dev/null
+++ b/HouseRobber.java
@@ -0,0 +1,54 @@
+class HouseRobber {
+    //T = O(n)
+    //space = O(1)
+    public int rob(int[] nums) {
+        if (nums.length ==1) return nums[0];
+        int n = nums.length;
+        // int[] dp = new int[n];
+        int prev = nums[0];
+        int curr = Math.max(nums[0],nums[1]);
+        for (int i=2; i<n; i++){
+            int temp = curr;
+            curr= Math.max(curr,prev+nums[i]);
+            prev = temp;
+        }
+        return curr;
+
+    }
+}
+
+// class Solution {
+//     //T = O(n)
+//     //space = O(n)
+//     public int rob(int[] nums) {
+//         if (nums.length ==1) return nums[0];
+//         int n = nums.length;
+//         int[] dp = new int[n];
+//         dp[0] = nums[0];
+//         dp[1] = Math.max(nums[0],nums[1]);
+//         for (int i=2; i<n; i++){
+//             dp[i] = Math.max(dp[i-1],dp[i-2]+nums[i]);
+//         }
+//         return dp[n-1];
+
+//     }
+// }
+
+
+//O(2^n)
+// class Solution {
+//     public int rob(int[] nums) {
+//         if (nums.length ==1) return nums[0];
+//         return helper(nums, 0);
+//     }
+//     private int helper(int[] nums, int idx) {
+//         //base
+//         if (idx >= nums.length) return 0;
+        
+//         //logic
+//         int case0 = helper(nums, idx+1);
+//         int case1 = nums[idx] + helper(nums,idx+2);
+    
+//         return Math.max(case0, case1);
+//     }
+// }
\ No newline at end of file

From b36bf8709b2fb6f3c75e13006a163947397fd3c8 Mon Sep 17 00:00:00 2001
From: Joshua Yoon <joshyoon92@gmail.com>
Date: Mon, 15 Jun 2026 17:59:35 -0500
Subject: [PATCH 3/3] dp-1 new commit

---
 CoinChange.java  | 1 +
 HoseRobber2.java | 1 +
 HouseRobber.java | 1 +
 3 files changed, 3 insertions(+)

diff --git a/CoinChange.java b/CoinChange.java
index 34ea419f..b470ac53 100644
--- a/CoinChange.java
+++ b/CoinChange.java
@@ -1,4 +1,5 @@
 public class CoinChange<T> {
+    
     public int coinChange(int[] coins, int amount) {
         int col = amount;
         int[] dp = new int[col+1];
diff --git a/HoseRobber2.java b/HoseRobber2.java
index d50774e6..2dd3978d 100644
--- a/HoseRobber2.java
+++ b/HoseRobber2.java
@@ -1,4 +1,5 @@
 public class HoseRobber2 {
+    
     public int robber(int[] nums) {
         int[][] dp = new int[nums.length + 1][2];
         dp[0][1] = 0;
diff --git a/HouseRobber.java b/HouseRobber.java
index b6ce878d..ae9872ff 100644
--- a/HouseRobber.java
+++ b/HouseRobber.java
@@ -1,5 +1,6 @@
 class HouseRobber {
     //T = O(n)
+    
     //space = O(1)
     public int rob(int[] nums) {
         if (nums.length ==1) return nums[0];