Added 'trapping-rain-water' challenge

Author: krnbhargav

trapping-rain-water/.solve.py.swp

@@ -0,0 +1,21 @@
+from typing import List
+class Solution:
+  def trap(self,height:List[int]) -> int:
+    ans=0
+    if len(height) < 3:
+      return 0
+    left,right = 0,len(height) - 1
+    left_max ,right_max= height[left],height[right]
+    while (left < right):
+      left_max = max(left_max,height[left])
+      right_max = max(right_max,height[right])
+      if left_max < right_max:
+        ans+= left_max - height[left]
+        left += 1
+      else:
+        ans+= right_max - height[right]
+        right -= 1
+    return ans
+if __name__ == "__main__":
+  s = Solution()
+  print(s.trap([4,2,0,3,2,5]))