top button
Flag Notify
    Connect to us
      Facebook Login
      Site Registration Why to Join

Facebook Login
Site Registration

Reverse the words in a string without changing their order?

+6 votes

Say you are given "Hello World"
Output should be "olleH dlroW"

related to an answer for: Reverse the order of the words
posted Oct 30, 2013 by Salil Agrawal

Share this question
Facebook Share Button Twitter Share Button LinkedIn Share Button
Example string "Hello World"
Start reading original string character by character and push it in a stack of characters and also mark start of the current word(start =0 for the first word). If reached space start popping characters from stack and copy them the start point marked, and update start(start = 6) with loop_counter + 1(loop_counter will be 5 at this time as space is at index 5).

Comments invited

3 Answers

0 votes

Python code

import re
text = "This is a text for testing !"

for m in re.finditer(r"\w+", text):
     text = text[0:m.start()] + text[m.start():m.end()][::-1] +text[m.end():]

print text
answer Oct 30, 2013 by Pankaj Agarwal
0 votes

See this simple program where I am managing the boundary and just reversing the characters within the boundary and it works

#include <stdio.h>

void reverse(char *begin, char *end)
  char temp;
  while (begin < end)
    temp = *begin;
    *begin++ = *end;
    *end-- = temp;

void reverseWords(char *s)
  char *word_begin = s;
  char *temp = s;

  while( *temp )
    if (*temp == '\0')
    else if(*temp == ' ')
      reverse(word_begin, temp-1);
      word_begin = temp+1;

        char words[] = "this is a test";
        printf("%s\n", words);
answer Jul 4, 2014 by Tapesh Kulkarni
–1 vote

Try this its working fine in C using recursion

#include <stdio.h>

void reverse();

void main() {      
        printf("Please enter a sentence: ");

void reverse() {    
        char c;
        if(c != '\n') {      
answer Jul 4, 2014 by Gaurav Maurya
Similar Questions
+6 votes

Given an array of characters which form a sentence of words, give an efficient algorithm to reverse the order of the words (not characters) in it

0 votes

Suppose you are given "Luv you 123 luv me" the expected output is "vuL uoy 123 vul em"

+3 votes

Is it possible if yes can someone share the code in C?

+2 votes

e.g 1. "hello how are you" - distance between "hello" and "you" is 3.
e.g 2. "hello how are hello you" - distance is 1
e.g 3. "you are hello" - distance is -1. Order of "hello" and "you" should be preserved.
e.g 4. "hello how are hello" - distance is -1 since "you" did not occur even once.

Contact Us
+91 9880187415
#280, 3rd floor, 5th Main
6th Sector, HSR Layout
Karnataka INDIA.