CareerCup

Sorry!!
The above is for another post, replacing 'a' with 'one' and 'A' with 'ONE'.
However, for this post, the clue is the same.
btw: I don't quite understand how vijay's code could solve the problem.
Maybe vijay could explain more.

import java.io.*;
import java.util.*;

class replace
{
public static void main(String [] args)
{
String totest[];
int i;
String test="She is a Hot girl";
String newString="";
StringTokenizer st= new StringTokenizer(test);

while(st.hasMoreTokens())
{
String temp=st.nextToken();
if( temp.compareTo("a")==0)
newString=newString+"the ";
else
newString= newString+ temp + " ";

}
System.out.println(newString);

}
}

#include<iostream>
#include<cstdlib>
#include<cstring>

using namespace std;

int main(){

char str[]="a apple is a fruit and I like apple";
char *pch;
string newstr="";
/*init of newstr:two conditions*/
if(str[0]=='a'){
newstr="the";
}

cout<<str<<endl;
pch=strtok(str,"a");
newstr+=pch;

pch=strtok(NULL,"a");
while(pch!=NULL){
newstr+="the";
newstr+=pch;
pch=strtok(NULL,"a");
}
cout<<newstr<<endl;

return 0;
}

public class StrReplace {

public static String replace (String str, String toR, String r) {
String[] words= str.split(" ");
StringBuffer ret = new StringBuffer ( );
for (int i=0; i<words.length; i++) {
if ((words[i].toLowerCase()).equals(toR.toLowerCase())) {
if (i==0) { //make the first letter upper case
ret.append(r.substring(0, 1).toUpperCase());
ret.append(r.substring(1));
} else {
ret.append(r);
}
ret.append(" ");
} else {
ret.append(words[i]);
ret.append(" ");
}
}
return ret.toString();
}

public static void main(String [] args) {
String str = "A quick brown fox jumped over a bridge on a box.";
String toR = "a";
String r = "the";
System.out.println(StrReplace.replace(str, toR, r));
}
}

// program to replace a with the
//logic - iteration1 - count a in the string...
//      - iteration 2 - start from end of the string,shifting the contents by 
//                      number of 'a'* 2(becasue of t'he'),and keep on decreasing
//                      count value till we reach 0

#include<stdio.h>
#include<stdlib.h>

void main(){

        char a[100];
        int count = 0, i = 0, moves = 0;
        printf("\n Enter a string ");
        gets(a);
        printf("\n string enterend is %s\n",a);
        // counting number of 'a's in the string
        while(a[i]!='\0'){
                if(a[i] == 'a' && ((a[i+1] == ' ' && a[i-1] == ' ' && i!=0 )|| (i==0 && a[i+1] == ' ') || (a[i+1] == '\0' && a[i-1] == ' '  ) ) )
                        count++;
                i++;
        }
 printf("\n length of the string : %d, and number of moves :%d",i,count);
        while(count != 0 ){
                //number of moves from back 
                moves = count * 2;

                a[i+moves] = a[i];
                if(a[i] == 'a' && ((a[i+1] == ' ' && a[i-1] == ' ' && i!=0 )|| (i==0 && a[i+1] == ' ')|| (a[i+1] == '\0' && a[i-1] == ' ' ) ) ){
                        a[i+moves] = 'e';
                        a[i+moves-1] = 'h';
                        a[i+moves-2] = 't';
                        count--;
                        }
                i--;
printf("\n The string is %s\n",a);
}

// program to replace a with the
//logic - iteration1 - count a in the string...
//      - iteration 2 - start from end of the string,shifting the contents by 
//                      number of 'a'* 2(becasue of t'he'),and keep on decreasing
//                      count value till we reach 0

#include<stdio.h>
#include<stdlib.h>

void main(){

        char a[100];
        int count = 0, i = 0, moves = 0;
        printf("\n Enter a string ");
        gets(a);
        printf("\n string enterend is %s\n",a);
        // counting number of 'a's in the string
        while(a[i]!='\0'){
                if(a[i] == 'a' && ((a[i+1] == ' ' && a[i-1] == ' ' && i!=0 )|| (i==0 && a[i+1] == ' ') || (a[i+1] == '\0' && a[i-1] == ' '  ) ) )
                        count++;
                i++;
        }
 printf("\n length of the string : %d, and number of moves :%d",i,count);
        while(count != 0 ){
                //number of moves from back 
                moves = count * 2;

                a[i+moves] = a[i];
                if(a[i] == 'a' && ((a[i+1] == ' ' && a[i-1] == ' ' && i!=0 )|| (i==0 && a[i+1] == ' ')|| (a[i+1] == '\0' && a[i-1] == ' ' ) ) ){
                        a[i+moves] = 'e';
                        a[i+moves-1] = 'h';
                        a[i+moves-2] = 't';
                        count--;
                        }
                i--;
printf("\n The string is %s\n",a);
}

public static void main(String args[])
	{
		
		String test="A quick brown fox jumped over a bridge on a box";
		StringBuilder output=new StringBuilder();
		StringTokenizer st=new StringTokenizer(test);
		
		while(st.hasMoreTokens())
		{
			String temp=st.nextToken();
			
			if(temp.compareTo("A")==0)
			{
				output.append(" The ");
				
				
			}
			else
			if(temp.compareTo("a")==0)
			{
				output.append(" the ");
				
				
			}
			else
				output.append(temp+" ");
				
		}
		
		System.out.println(output);
	}

#include <iostream>
#include <string.h>


using namespace std;

int main() {

	char input[] ="a person who is a boy is a man";
	string new_string= "";
	char deli [] = " ";


	char *position;
	position = strtok(input, deli);
	while (1)
	{

		if (strcmp(position,"a")==0)
			new_string += "the ";
		else
		{
			new_string += position;
			new_string += " ";
		}
		position = strtok(NULL, deli);
		if (position==NULL)
			break;

	}
	cout<<new_string;

}

int main()
{
char a[] = "He is a man";
char b[100];
int i,j;
j=strlen(a);

for(i=0;i<j;i++)
{
if(a[i]=='a')
{
b[k++]='t';
b[k++]='h';
b[k++]='e';
}
else
{
b[k++]=a[i];
}
}

k=0;
while(b[k]!='\0')
{
printf("%c",b[k]);
k++;
}
}

Python working code.

"""
@Python 2.7

Given a string...replace all occurances of a with the. 
eg. A quick brown fox jumped over a bridge on a box. 
should change to 
The quick brown fox jumped over the bridge on the box. 
You cannot use the inbuilt replace function for string manipulation.

- Troy on October 07, 2010 Report Duplicate | Flag 
"""

class AtoThe(object):
  def __init__(self, inputs):
    if inputs is None:
      print 'invalid inputs'
    self._input = inputs
      
  def fromAToThe(self):
    input = self._input.split()
    output = []
    for c in input:
      if c == 'a':
        output.append('the')
      elif c == 'A':
        output.append('The')
      else:
        output.append(c)
        
    return ' '.join(output)
    
if __name__ == '__main__':
  a = AtoThe('A quick brown fox jumped over a bridge on a box.')
  print a.fromAToThe()

Here is a working code in C++. I have assumed that we need not replace the occurrence of 'a' when it is a part of another word. We only replace it when 'a' itself is a word.

#include<cstdio>
#include<iostream>
#include <string.h>

using namespace std;

int main()
{
    char str[100];
    int i;
    scanf("%[^\n]s", str);
    for (i=0; i<strlen(str); i++)
    {
        if (i==0 && (str[i]=='a' || str[i]=='A') && str[i+1]==' ')
        {
            cout<<"The";
        }
        else if((str[i]=='a' || str[i]=='A') && str[i+1]==' ' && str[i-1]==' ')
        {
            cout<<"The";
        }
        else if (i==(strlen(str)-1) && (str[i]=='a' || str[i]=='A') && str[i-1]==' ')
        {
            cout<<"The";
        }
        else
        {
            cout<<str[i];
        }
    }
    return 0;
}

import java.util.*;
public class ReplaceA{
	
	public static void main(String args[]){

		String str = "A quick brown fox jumped over a bridge on a box";

		StringTokenizer token = new StringTokenizer(str," ");
		String newString = "";

		while(token.hasMoreTokens()){
				String tempString = token.nextToken();
				if(tempString.equalsIgnoreCase("A")){
					tempString = "The";
				}
				newString = newString + " " + tempString;
			}

			System.out.println(newString);
		}

		

	}

Much simpler..

public class epic28 {
	public static void main(String[] args) {
		// TODO Auto-generated method stub
		String str = "A quick brown fox jumped over a bridge on a box";
		String[] st = str.split(" ");
		
		for(int i = 0;i < st.length;i++)
			if(st[i].equalsIgnoreCase("a"))
				st[i] = "the";
		
		for(int i = 0;i < st.length-1;i++)
			System.out.print(st[i]+" ");
		
		System.out.print(st[st.length-1]+" ");
	}

}

sed 's/\ba\b/one/g'

use
#define "a" "the"
#define "the" "a"

scan the whole array and print the desired one.

use
#define "a" "the"
#define "the" "a"

scan the whole array and print the desired one.

#include<string.h>
#include<vector.h>
#include<iostream>
#include<stdlib.h>
int main() {
std::string NewStr;
std::string OrigStr=std::string("A boy is playing in a garden.");
std::size_t LengthStr = OrigStr.length();
OrigStr = ' '+OrigStr;
OrigStr = OrigStr+' ';
for (int i=1; i<LengthStr+1; i++) {
if(OrigStr[i-1]==' '&&OrigStr[i+1]==' ') {
if (OrigStr[i]=='a') {
NewStr.push_back('o');
NewStr.push_back('n');
NewStr.push_back('e');
} else if(OrigStr[i]=='A') {
NewStr.push_back('O');
NewStr.push_back('N');
NewStr.push_back('E');
} else NewStr.push_back(OrigStr[i]);
} else NewStr.push_back(OrigStr[i]);
}
return 0;
}

#include <iostream>
#include <string>
using namespace std;


int main()
{
	string s = "I am a boy.";
	string temp;
	cout<<s<<endl;
	for (int i=0; i<s.length(); ++i)
	{
		if (s[i]=='a')
		{
			temp.push_back('o');
			temp.push_back('n');
			temp.push_back('e');
		}

		else
		{
			temp.push_back(s[i]);
		}
	}
	
	cout<<temp<<endl;
	system("pause");
	return 0;
}