Added solutions:

Author: avidLearnerInProgress

amazon/vertical_sum.cpp

@@ -0,0 +1,110 @@
+{
+#include<bits/stdc++.h>
+using namespace std;
+struct Node
+{
+	int data;
+	struct Node *left;
+	struct Node *right;
+	
+	Node(int x){
+	    data = x;
+	    left = NULL;
+	    right = NULL;
+	}
+};
+void insert(Node *root,int a1,int a2,char lr){
+	if(root==NULL)
+		return;
+	if(root->data==a1){
+		switch(lr){
+			case 'L':root->left=new Node(a2);
+			break;
+			case 'R':root->right=new Node(a2);
+			break;
+		}
+	}
+	else{
+		insert(root->left,a1,a2,lr);
+		insert(root->right,a1,a2,lr);
+	}
+}
+int mn=0;
+int aa[10000];
+void printVertical(Node *root);
+int main(){
+	int t;
+	cin>>t;
+	while(t--){
+		memset(aa,0,sizeof(aa));
+		int n;
+		cin>>n;
+		mn=0;
+		Node *root=NULL;
+		while(n--){
+			int a1,a2;
+			char lr;
+			cin>>a1>>a2;
+			scanf(" %c",&lr);
+			if(root==NULL){
+				root=new Node(a1);
+				switch(lr){
+					case 'L':root->left=new Node(a2);
+					break;
+					case 'R':root->right=new Node(a2);
+					break;
+				}
+			}
+			else{
+				insert(root,a1,a2,lr);
+			}
+		}
+		printVertical(root);
+		cout<<endl;
+	}
+}
+}
+/*This is a function problem.You only need to complete the function given below*/
+/*Complete the function below
+Node is as follows:
+struct Node{
+int data;
+Node *left,*right;
+};
+*/
+
+map<int, int> m;
+void printVerticalUtil(Node *root, int hd){
+    if(!root) return;
+    m[hd] += root->data;
+    printVerticalUtil(root->left, hd - 1);
+    printVerticalUtil(root->right, hd + 1);
+}
+
+void printVertical(Node *root)
+{
+//add code here.
+    if(!root) return;
+    /*
+    queue<pair<Node*, int>> q; //node and its horizontal distance
+    map<int, int> m; //distance
+    
+    q.push({root, 0});
+    
+    while(!q.empty()){
+        pair<Node*, int> p = q.front();
+        Node* curr = p.first;
+        int hd = p.second;
+        m[hd] += curr->data;
+        
+        if(curr->left != NULL)
+            q.push({curr->left, hd - 1});  
+        if(curr->right != NULL)
+            q.push({curr->right, hd + s1});
+    }*/
+    printVerticalUtil(root, 0);
+    
+    for(auto it = m.begin(); it != m.end(); it++)
+        cout<<it->second<<" ";
+    m.clear();
+}

count_palindromic_substrings.py

@@ -0,0 +1,11 @@
+class Solution:
+        def countSubstrings(self, s):
+
+            leftrights = [(x,x) for x in list(range(len(s)))] + [(x,x+1) for x in list(range(len(s)-1))]
+            count = 0
+            for left, right in leftrights:
+                while left >= 0 and right < len(s) and s[left]==s[right]:
+                    count += 1
+                    left -= 1
+                    right += 1
+            return count