CareerCup

Reverse the individual strings before the white space
Example :
I am boy
I ma yob

after reverseral of each individual string reverse the entire string
o/p
boy am I
Example 2

Hello Life
a) olleH efiL
b) Life Hello
Note :
In place algorithm..No extra space needed...

1> Push individual words (like Hello,life) into stack
2> Just pop it..

In-place implementation of the reverse sentence words. Algorithm description inlined in s/c.

#include <stdio.h>
#include <string.h>

void rev_string(char *dat, int len)
{
	char *ps, *pe, tmp;

	if (1 == len)
		return;

	ps = dat; // the start of the data
	pe = dat + len - 1; // the end (last char) of the data

	while (ps < pe) {
		tmp = *ps;
		*ps = *pe;
		*pe = tmp;
		ps++;
		pe--;
	}    
}

/** 
    Do an in-place reversing of the words in sentence,eg.
    "1234 56  78 9" -> "9 78  56 1234" 

    Algorithm:
    1. Reverse the whole string
    2. Scan the resulting sentence from left to right and:
    a) Find each token (word delimited by whitespace)
    b) Reverse each token
    c) Loop back to a) while there are more tokens 
*/
void rev_sentence_words(char dat[], int len)
{
	int i, j;
	char *ps;

	rev_string(dat, len);

	for (i = 0; i < len; i++) {
		if (dat[i] == ' ')
			continue;
		j = i;
		ps = &dat[j];

		/* Find the next whitespace */
		while (dat[i] && dat[i] != ' ')
			i++; 
		rev_string(ps, i - j);
	}
}

int main(int argc, char* argv[])
{
	char dat[] = " the careercup just rocks ";

	printf("Before: <%s>\n", dat);
	rev_sentence_words(dat, strlen(dat));
	printf("After: <%s>\n", dat);

	return 0;
}

This should be in place otherwise it will be trivial.

Take another array of same size.
push each word at the end of the new array.
Given Array.am i right
Result Array.

1.            am
2.        i  am 
3. right i am

void reverse(char* start, char* end)
{
while (start < end)
{
char tmp = *end;
*end = *start;
*start = tmp;

start++;
end--;
}
};

int main()
{
char str[] = "I love you";
char* start = str;
char* end = str + 1;
while(end <= start + 10)
{
if(*end == '\0' || *end == ' ')
{
reverse(start, end - 1);
start = end + 1;
}
end++;
}
reverse(str, str + 9);
printf("%s", str);
return 0;
}

#include<iostream>
#include<string>

void reverse(char *a, int i, int j)
{
if(i>j)
{
int temp=i;
i=j;
j=temp;
}
char temp;
while(i<j)
{
temp=a[i];
a[i]=a[j];
a[j]=temp;
i++;
j--;
}
}

void reversesentence(char * a, int length) //assumption
{
int i=0;
int j=0;
while(j<length-1)
{
while(a[j]==' '&&j<length-1)
{
j++;
i=j;
}
while(a[j]!=' '&&j<length-1)
{
j++;
}
if(a[j]==' ')
{
j--;
}
reverse(a,i,j);//first blank
j++;
i=j;
}
reverse(a,0,length-1);
}

void main()
{
char a[]=" i am lucky ";
reversesentence(a,strlen(a));
puts(a);
}

char str[] = "Hello World";
char str2[] = "";
int i;
for(i=strlen(str)-1; i<=0; i--)
{
  if(str[i]==' ')
  {
    strcat(str2,str+i+1);
    strcat(str2," ");
    str[i]=0;  // cut
  }
}
// first that becomes last
strcat(str2,str);
printf("\n str: %s", str2);

//let input be the line read from any form input method you can think of e.g. sc or filereader

String[] array = input.split(" ");
for(int x = array.length()-1; x >=0; x--){
System.out.print(array[x] + " ");
}
System.out.println();

Reverse words, reverse sentance algo is great.
Here is another:
Time: O(2n)
Space: (On)

private static char[] ReverseWordsInSentance(char[] input)
        {
            if (input == null || input.Length < 2) return input;
            var output = new char[input.Length];
            var outputRunner = 0;
            var latestLimit = input.Length;
            for(int i = input.Length - 1; i >= -1; --i)
            {
                if(i==-1 || input[i] == ' ')
                {
                    for (int j = i + 1; j < latestLimit; ++j)
                    {
                        output[outputRunner++] = input[j];
                    }
                    if(i != -1)
                    {
                        latestLimit = i;
                        output[outputRunner++] = ' ';
                    }
                }
            }
            return output;
        }

import java.util.ArrayList;

public class StringToStringArray {

	/**
	 * @param args
	 */
	public static void main(String[] args) {

		char[] a = "Hello World How are you".toCharArray();
		ArrayList<String> myArrayList = new ArrayList<String>();
		boolean isFinalCharSpace = false;

		//get String array from Char array
		StringBuilder sb = new StringBuilder();
		int j = 0;
		for (int i = 0; i < a.length; i++) {

			isFinalCharSpace = false;
			if (a[i] != ' ') {
				sb.append(a[i]);
			} else if (a[i] == ' ') {
				if (sb.length() > 0) {
					myArrayList.add(sb.toString());
				} else {
					myArrayList.add(" ");
				}
				j++;
				sb.setLength(0);
				isFinalCharSpace = true;
			}
		}

		if (!isFinalCharSpace) {
			myArrayList.add(sb.toString());
			j++;
			sb.setLength(0);
		}

		int length = myArrayList.size();

		//swap the corresponding elements
		for (int k = 0; k < length / 2; k++) {
			String temp = myArrayList.get(k);
			myArrayList.set(k, myArrayList.get(length - 1 - k));
			myArrayList.set(length - 1 - k,temp);
		}

	}

}

reverse the whole string , put in the stack , pop it out word by word

Reverse the whole sentence and then reverse the output word by word
CODE :

void reverseWordByWord (char *str) {
	char *start = str;
	int len = strlen(str);
	char *end = str+len-1;

	reverse(start, end);
	int i;
	for (i=0; i<len; i++) {
		if (str[i]== ' ') {
			end = &str[i-1];
			reverse(start,end);
			start = &str[i+1];
		}
	}
	//Reverse the last word !
	end = &str[i-1];
	reverse(start,end);

}

Split the string by white spaces to an array.
Call Array.reverse
return the joined array by white space