diff --git a/128-longest-consecutive-sequence.cpp b/128-longest-consecutive-sequence.cpp
new file mode 100644
index 0000000..6a9886e
--- /dev/null
+++ b/128-longest-consecutive-sequence.cpp
@@ -0,0 +1,27 @@
+//128-longest-consecutive-sequence.cpp
+class Solution {
+public:
+    int longestConsecutive(vector<int>& arr) {
+        int n = arr.size(); 
+        if(n == 0) return 0;
+        
+        sort(arr.begin(), arr.end());
+        
+        int mxLen = 0, currLen = 1; 
+        
+        for(int i = 1; i < n; i++) 
+        {
+            if(arr[i] == arr[i - 1] + 1) 
+            {
+                currLen++; 
+            }
+            else if(arr[i] != arr[i - 1])
+            {
+                mxLen = max(mxLen, currLen);
+                currLen = 1;
+            }
+        }
+        mxLen = max(mxLen, currLen);
+        return mxLen;
+    }
+};
diff --git a/198-house-robber.cpp b/198-house-robber.cpp
new file mode 100644
index 0000000..f69fb60
--- /dev/null
+++ b/198-house-robber.cpp
@@ -0,0 +1,19 @@
+//198-house-robber.cpp
+
+class Solution {
+public:
+    int solve(vector<int>& nums, int i, vector<int>& dp)
+    {
+        if(i>=nums.size())
+            return 0;
+        if(dp[i]!=-1)
+            return dp[i];
+        return dp[i]=max(solve(nums,i+1,dp), nums[i]+ solve(nums,i+2,dp));
+    }
+    
+    int rob(vector<int>& nums) 
+    {
+        vector<int> dp(nums.size()+1,-1);
+        return solve(nums,0,dp);
+    }
+};