# check if string is palindrome hackerrank

... 1 if it’s impossible to create a palindrome under the constraints. Our task is to find if there exists a substring in the given string that is a palindrome and is of even length. When an inequality occurs, ->skip the right element and check the middle portion of the string including the left element if it's a palindrome. ; The length of is as long as possible. If found, we return 1 otherwise 0. A palindrome consists of a char c, followed by a string that must be empty or palindromic, followed by another c, if it's longer than 1 char. Pretty simple: we can derive a rules that allow checking whether the string is palindromic in O(n). ; For each of the pairs of strings (and ) received as input, find and print string on a new line. We will check both the cases, remember as we have traversed equal number of steps from both sides, this mid string should also be a palindrome after removing one character, so we check two substrings, one by removing left character and one by removing right character and if one of them is palindrome then we can make complete string palindrome by removing corresponding character, and … Learn to check if a given string is palindrome string with simple java programs using stack, queue or simple loops. This one comes from HackerRank. If we use brute-force and check whether for every start and end position a substring is a palindrome we have O(n^2) start - end pairs and O(n) palindromic checks. Examples: Input : malayalam Output : Yes Input : geeks Output : No Given a string, write a c function to check if it is palindrome or not. The best way to solve this problem is by looking at it from both ends just like you would while checking for the string being a palindrome. To read the full prompt, navigate to HackerRank Palindrome Index Question.. palindrome = x.palindrome.x | x | x.x , where x is an arbitrary token So how does that help us? ; is a palindromic string. You will be given a string representation of a number and a maximum number of changes you can make. When length of string is odd: Only one character occurs odd number of times in the string, other characters occur even number of times. Suppose, we are given a string that contains only lowercase letters. Palindromes are strings that read the same from the left or right, for example madam or 0110. Simple if the string is "MADAM" compare the First letter index of 'M' to the last letter index of 'M' and again compare to 2nd letter index to the second last letter index if both are same then continue for next upcoming letters and repeat the same process continue to repeat if all Word's are same then String Is Palindrome. Given a string, write a python function to check if it is palindrome or not. For example, “abba” is palindrome, but “abbc” is not palindrome. In simplest words, a string is palindrome if it is equal to it’s reverse string.. A palindrome is a word, phrase, number, or other sequence of units that may be read the same way in either direction, generally if used comma, separators or other word dividers are ignored. You have two strings, and .Find a string, , such that: can be expressed as where is a non-empty substring of and is a non-empty substring of . Alter the string, one digit at a time, to create the string representation of the largest number possible given the limit to the number of changes. This can be done in O(n) where n is the length of string. So to check whether a string can be a scatter palindrome or not, we just need to check the number of occurence of each character in the string. 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