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champ96k · champ96k · commit 32379da88ea5 · 2021-09-27T07:39:41.000+05:30
diff --git a/trapping-rain-water/trapping-rain-water.cpp b/trapping-rain-water/trapping-rain-water.cpp
@@ -0,0 +1,26 @@
+class Solution {
+public:
+    int trap(vector<int>& a) {
+        
+        int res = 0;
+        int n = a.size();
+        int lmax[n];
+        int rmax[n];
+        
+        lmax[0] = a[0];
+        for(int i=1;i<n;i++) {
+           lmax[i]=max(a[i],lmax[i-1]);
+        }
+        
+        rmax[n-1] = a[n-1];
+        for(int i=n-2;i>0;i--) {
+           rmax[i]=max(a[i],rmax[i+1]);
+        }
+        
+        for(int i=1;i<n;i++) {
+            res = res + (min(lmax[i],rmax[i])-a[i]);
+        }
+        
+        return res;
+    }
+};
