diff --git a/coin change.java b/coin change.java
new file mode 100644
index 00000000..5c716a88
--- /dev/null
+++ b/coin change.java	
@@ -0,0 +1,29 @@
+class Solution {
+     int[][] memo;
+    public int coinChange(int[] coins, int amount) {
+         int m = coins.length;
+        int n = amount;
+        this.memo = new int[m+1][n+1];
+
+        int re = helper(coins, 0, amount);
+
+        if(re == 99999) return -1;
+        return re;
+    }
+
+     private int helper(int[] coins, int i, int amount){
+        
+        if(amount < 0 || i == coins.length) return 99999;
+
+        if(amount == 0) return 0;
+
+        if(memo[i][amount] != 0 ) return memo[i][amount];
+
+        int case0 = helper(coins, i+1, amount);
+        int case1 = 1 + helper(coins, i, amount - coins[i]);
+      
+        memo[i][amount] = Math.min(case0, case1);
+        
+        return Math.min(case0, case1);
+    }
+}
\ No newline at end of file
diff --git a/house robber.java b/house robber.java
new file mode 100644
index 00000000..99ee0745
--- /dev/null
+++ b/house robber.java	
@@ -0,0 +1,16 @@
+class Solution {
+    public int rob(int[] nums) {
+        if(nums.length == 1) return nums[0];
+        if(nums.length == 2) return Math.max(nums[0],nums[1]);
+        int[] dp = new int[nums.length];
+         dp[0] = nums[0];
+        dp[1] = Math.max(nums[0],nums[1]);
+        for(int i = 2; i< nums.length; i++) {
+
+            int case0 = dp[i-1];
+            int case1 = nums[i] + dp[i-2];
+            dp[i]=Math.max(case0, case1);
+        }
+        return dp[nums.length-1];
+    }
+}
\ No newline at end of file