From eb96152654ed52de359309f434a716643b3892f8 Mon Sep 17 00:00:00 2001
From: StealthX2k20 <61972131+StealthX2k20@users.noreply.github.com>
Date: Sun, 28 Feb 2021 11:46:17 +0530
Subject: [PATCH] Solution to rain water trapping problem leetcode

---
 Interview/Trapping Rain Water.cpp | 44 +++++++++++++++++++++++++++++++
 1 file changed, 44 insertions(+)
 create mode 100644 Interview/Trapping Rain Water.cpp

diff --git a/Interview/Trapping Rain Water.cpp b/Interview/Trapping Rain Water.cpp
new file mode 100644
index 0000000..ca20888
--- /dev/null
+++ b/Interview/Trapping Rain Water.cpp	
@@ -0,0 +1,44 @@
+class Solution {
+public:
+    int trap(vector<int>& height) {
+        int prevMaxHeight, result = 0, curResult = 0, peakIndex;
+        
+        prevMaxHeight = 0;
+        
+        for(int i = 1; i < height.size(); i++)
+        {
+            if(height[i] < height[prevMaxHeight])
+            {
+                curResult += (height[prevMaxHeight] - height[i]);
+            }
+            
+            else
+            {
+                result += curResult;
+                curResult = 0;
+                prevMaxHeight = i;
+            }
+        }
+        
+        peakIndex = prevMaxHeight;
+        prevMaxHeight = height.size() - 1;
+        curResult = 0;
+        
+        for(int i = height.size() - 2; i >= peakIndex; i--)
+        {
+           if(height[i] < height[prevMaxHeight])
+            {
+                curResult += (height[prevMaxHeight] - height[i]);
+            }
+            
+            else
+            {
+                result += curResult;
+                curResult = 0;
+                prevMaxHeight = i;
+            }
+        }
+        
+        return result;
+    }
+};