From 2dac8976a248b0df6ac49be52b484d209250b490 Mon Sep 17 00:00:00 2001
From: iceweasel <johnsjosephk@pm.me>
Date: Mon, 17 Oct 2022 23:49:18 +0530
Subject: [PATCH] add 2 numbers and unique paths count

---
 Medium/02.Add2Numbers/Add2Numbers.cpp  | 41 ++++++++++++++++++++++++++
 Medium/62.UniquePaths/Unique_paths.cpp | 23 +++++++++++++++
 2 files changed, 64 insertions(+)
 create mode 100644 Medium/02.Add2Numbers/Add2Numbers.cpp
 create mode 100644 Medium/62.UniquePaths/Unique_paths.cpp

diff --git a/Medium/02.Add2Numbers/Add2Numbers.cpp b/Medium/02.Add2Numbers/Add2Numbers.cpp
new file mode 100644
index 0000000..8a66311
--- /dev/null
+++ b/Medium/02.Add2Numbers/Add2Numbers.cpp
@@ -0,0 +1,41 @@
+class Solution {
+public:
+    ListNode* addTwoNumbers(ListNode* l1, ListNode* l2) {
+        ListNode *headnode = new ListNode();
+        ListNode *result = headnode ;
+        
+        int carry = 0 , sum = 0   ; 
+        
+        while(l1 || l2){
+            
+             sum = 0 ; 
+            
+            if(l1){
+                sum += l1->val; 
+                l1 = l1->next ;
+            }
+            
+            if(l2){
+                sum += l2->val; 
+                l2 = l2->next ; 
+            }
+            
+            sum += carry ; 
+            
+            carry = sum > 9 ? 1: 0; 
+            sum %= 10 ; 
+            
+            ListNode *dNode = new ListNode(sum);
+            headnode->next = dNode ; 
+            headnode = dNode ;
+            
+        }
+        
+        if(carry){
+            ListNode *dNode = new ListNode(carry);
+            headnode->next = dNode; 
+            return result->next ;
+        }
+        return result->next ; 
+    }
+};
diff --git a/Medium/62.UniquePaths/Unique_paths.cpp b/Medium/62.UniquePaths/Unique_paths.cpp
new file mode 100644
index 0000000..de0459a
--- /dev/null
+++ b/Medium/62.UniquePaths/Unique_paths.cpp
@@ -0,0 +1,23 @@
+class Solution {
+public:
+    int solve(int m , int n , vector<vector <int>> &dp ){
+      if(m ==1 && n ==1)
+          return 1 ;
+          
+      if(!m || !n)
+          return 0;
+        
+       if(dp[m][n] != -1)
+           return dp[m][n] ;
+        
+        dp[m][n] = solve(m-1,n, dp) + solve(m ,n-1,dp) ;
+        
+        return dp[m][n] ;
+        
+    }
+    
+    int uniquePaths(int m, int n) {
+        vector<vector<int>> dp(m+1 ,vector<int>(n+1 ,-1));
+        return solve(m,n,dp) ;
+    }
+};