Reverse Words In A String

Posted: 5 Sep, 2020
Difficulty: Easy


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You are given a string of length N. You need to reverse the string word by word. There can be multiple spaces between two words and there can be leading or trailing spaces but in the output reversed string you need to put a single space between two words, and your reversed string should not contain leading or trailing spaces.

For example :

If the given input string is "  Welcome to   Coding  Ninjas", then you should return "Ninjas Coding to Welcome" as the reversed string has only a single space between two words and there is no leading or trailing space.
Input Format :
The first line of input contains a single integer T, representing the number of test cases or queries to be run. 
Then the T test cases follow.

The first and only one of each test case contains a string that you need to reverse word by word.
Output Format :
For every test case, print the reversed string such that there should be only one space between two strings and there should not be any trailing space.
Note :
Do not print anything. It has already been taken care of.
Constraints :
1 <= T <= 50
0 <= N <= 10^5

Time Limit: 1 sec
Approach 1
  • Create a String ans to store the reversed string.
  • Initialize a variable i to 0 and iterate the whole string through a while loop.
  • Skip initial spaces by just incrementing i.
  • Create a String that will store the current word.
  • Add the currentword and space at the beginning of ans.
  • After traversing the whole string, check if the length of ans is greater than 0 then return ans after removing the last space otherwise return an empty string.
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