Server Side Programming Articles - Page 1871 of 2650

Suppose we have a binary tree; we have to flatten it into linked list in place. So if the tree is like −The output tree will be −To solve this, we will follow these steps −ser prev := nullDefine a recursive function solve(), that will take root as input.if root is null, then returnsolve(right of root)solve(left of root)right of root := prev, left of root := nullprev := rootLet us see the following implementation to get better understanding −Example Live Demo#include using namespace std; class TreeNode{    public:    int val;    TreeNode *left, *right;    TreeNode(int data){     ... Read More

Suppose we have a binary tree; we have to find the Zigzag level order traversal. So for the first row, scan from left to right, then right to left from the second row, then again left to right and so on. So if the tree is like −The traversal sequence will be [[3], [20, 9], [15, 7]]To solve this, we will follow these steps −if the tree is empty, return empty listqueue := make a queue and insert root into the queue, create two empty lists res and res2, and set flag as Truewhile queue is not emptymake a list ... Read More

In this article we will see how to create a list of lists which contain string data types. The inner list themselves or of string data type and they may contain numeric or strings as their elements.Using strip and splitWe use these two methods which will first separate out the lists and then convert each element of the list to a string.Example Live Demolist1 = [ '[0, 1, 2, 3]', '["Mon", "Tue", "Wed", "Thu"]' ] print ("The given list is : " + str(list1)) print("") # using strip() + split() result = [k.strip("[]").split(", ") for k in list1] print ("Converting list ... Read More

The cmp() is part of the python standard library which compares two integers. The result of comparison is -1 if the first integer is smaller than second and 1 if the first integer is greater than the second. If both are equal the result of cmp() is zero.Below example illustrates different scenario showing the use of cmp() method.Example Live Demodef cmp(x, y):    return (x > y) - (x < y) #x>y x = 5 y = 3 print("The cmp value for x>y is : ",cmp(x, y),"") #xy is : 1 The cmp value for x

In this article we consider a dictionary where the values are presented as lists. Then we consider clearing those values from the lists. We have two approaches here. One is to use the clear methods and another is to designate empty values to each key using list comprehension.Example Live Demox1 = {"Apple" : [4, 6, 9, 2], "Grape" : [7, 8, 2, 1], "Orange" : [3, 6, 2, 4]} x2 = {"mango" : [4, 6, 9, 2], "pineapple" : [7, 8, 2, 1], "cherry" : [3, 6, 2, 4]} print("The given input is : " + str(x1)) # using loop + ... Read More

In this article we will see how to find the frequency of each character in a given string. Then see if two or more characters have the same frequency in the given string or not. We will accomplish this in two steps. In the first program we will just find out the frequency of each character.Frequency of each characterHere we find the frequency of each character in the given input screen. We declare a empty dictionary and then add each character as a string. We also assign keys to each of the character to create the key-value pair needed by ... Read More

During analysis of data sets we may come across situations where we have to deal with empty dictionaries. In tis article we will see how to check if a dictionary is empty or not.Using ifThe if condition evaluates to true if the dictionary has elements. Otherwise it evaluates to false. So in the below program we will just check the emptiness of a dictionary using only the if condition.Example Live Demodict1 = {1:"Mon", 2:"Tue", 3:"Wed"} dict2 = {} # Given dictionaries print("The original dictionary : " ,(dict1)) print("The original dictionary : " ,(dict2)) # Check if dictionary is empty if dict1: ... Read More

In python data analysis, we sometime face a situation where we need to compare a given number with a list containing many values. In this article we need to fins if a given number is less than each of the values present in a given list. We are going to achieve it using the following two ways.Using for loopWe iterate through the given list and compare the given value with each of the values in the list. Once all values from the list are compared and the comparison condition holds good in each of the step, we print out the ... Read More

In this article we are going to see a python program that will give output of possible words from a given set of characters. Here we are taking a list as an input which will contain the set of reference words and another list containing the characters from which the words are made up of.In the below program, we define two functions. One to take the letters from the second list and make up words. Another function to match the words formed with the words present in the given list of words.Example Live Demodef Possible_Words(character):    x = {}    for ... Read More

We can access the individual elements of a list using the [] brackets and the index number. But when we need to access some of the indices then we cannot apply this method. We need the below approaches to tackle this.Using two listsIn this method, along with the original list, we take the indices as another list. Then we use a for loop to iterate through the indices and supply those values to the main list for retrieving the values.Example Live Demogiven_list = ["Mon", "Tue", "Wed", "Thu", "Fri"] index_list = [1, 3, 4] # printing the lists print("Given list : ... Read More