From 3066465cef8119dc2dfeb822f8e30b5daa99d20c Mon Sep 17 00:00:00 2001
From: geeky-hypertext629
 <107639960+geeky-hypertext629@users.noreply.github.com>
Date: Thu, 5 Oct 2023 22:11:50 +0530
Subject: [PATCH] Added Leetcode C++ Trapping Rain Water Problem

---
 README.md                       |  1 +
 codes/cpp/TrappingRainWater.cpp | 25 +++++++++++++++++++++++++
 2 files changed, 26 insertions(+)
 create mode 100644 codes/cpp/TrappingRainWater.cpp

diff --git a/README.md b/README.md
index 953596d..4417740 100644
--- a/README.md
+++ b/README.md
@@ -34,6 +34,7 @@
 | Serialize and Deserialize BST | [Leetcode](https://leetcode.com/problems/serialize-and-deserialize-bst/) | [YouTube](https://www.youtube.com/watch?v=-YbXySKJsX8&t=613s)|[C++](https://github.com/ShreemoyeeMukherjee/ProjectAlgorithms/blob/ShreemoyeeMukherjee-patch-2/Serialize%20and%20Deserialize%20BST) |
 | Construct Binary Search Tree from Preorder Traversal | [LeetCode](https://leetcode.com/problems/construct-binary-search-tree-from-preorder-traversal/) | [YouTube](https://www.youtube.com/watch?v=UmJT3j26t1I&t=692s) | [C++](https://github.com/ShreemoyeeMukherjee/ProjectAlgorithms/blob/ShreemoyeeMukherjee-patch-2/codes/cpp/Construct%20Binary%20Search%20Tree%20from%20Preorder%20Traversal) |    
 | First Unique Character in a String | [LeetCode](https://leetcode.com/problems/first-unique-character-in-a-string/) | [YouTube](https://www.youtube.com/watch?v=St47WCbQa9M) | [Java](./codes/java/FirstUniqueCharacterinaString.java) |    
+| Trapping Rain Water | [LeetCode](https://leetcode.com/problems/trapping-rain-water/description/) | [YouTube](https://www.youtube.com/watch?v=m18Hntz4go8) | [C++](./codes/cpp/TrappingRainWater.cpp) |    
 | Interleaving Strings | [LeetCode](https://leetcode.com/problems/interleaving-string/) | [YouTube](https://www.youtube.com/watch?v=3Rw3p9LrgvE) | [Python](./codes/python/InterleavingStringsProg.py) |    
 | Group Anagrams | [LeetCode](https://leetcode.com/problems/group-anagrams/) | [YouTube](https://www.youtube.com/watch?v=ptgykfAEax8) | [Java](./codes/java/GroupAnagramsProg.java) |    
 | Binary Tree Right Side View | [LeetCode](https://leetcode.com/problems/binary-tree-right-side-view/) | [YouTube](https://www.youtube.com/watch?v=jCqIr_tBLKs&t=390s) | [C++](./codes/cpp/BinaryTreeRightSideViewProg.cpp) |  
diff --git a/codes/cpp/TrappingRainWater.cpp b/codes/cpp/TrappingRainWater.cpp
new file mode 100644
index 0000000..185bbc9
--- /dev/null
+++ b/codes/cpp/TrappingRainWater.cpp
@@ -0,0 +1,25 @@
+#include<bits/stdc++.h>
+class Solution {
+public:
+    int trap(vector<int>& height) {
+        vector<int> lmax(height.size(),0);
+        vector<int> rmax(height.size(),0);
+        int i;
+        lmax[0]=height[0];
+        for(i=1;i<height.size();i++)
+        {
+            lmax[i]=max(lmax[i-1],height[i]);
+        }
+        rmax[height.size()-1]=height[height.size()-1];
+        for(i=height.size()-2;i>=0;i--)
+        {
+            rmax[i]=max(rmax[i+1],height[i]);
+        }
+        int res=0;
+        for(i=0;i<height.size();i++)
+        {
+            res+=min(lmax[i],rmax[i])-height[i];
+        }
+        return res;
+    }
+};
\ No newline at end of file