Largest Even Number

PROBLEM :
As usual Babul is back with his problem but this time with numbers. In his problem there is a number P (always a whole number) with N digits. Now he started finding out the largest possible even number formed by rearranging this N digit number. For example consider number 1324, after rearranging the digits the largest even number possible is 4312.

Note: In case the number does not contain any even digit then output the largest odd number possible.

Input:
The first line of input will contain an integer T which is the no. of test cases. Each of the next T lines will contain a number P.

Output:
For each test case in a new line print the required result.

Constraints:
1<=T<=100
1<=N<=1000

Example:

Input:
5
1324
3415436
1023422
03517
3555

Output:
4312
6543314
4322210
75310
5553

--------------------------------------------------------------------------------
SIMPLE c++ IMPLEMENTATION :
--------------------------------------------------------------------------------

#include<iostream>
using namespace std;
#include<string.h>
#include <string>
#include <stdlib.h>
string Largest_Even_Number(string) ;
string sort(string,int ) ;
int main()
 {
int t ;
string str ;
cin>>t ;
while(t--)
{
   cin>>str ;
   str=Largest_Even_Number(str) ;
   cout<<str<<endl ;
}
return 0;
}

string Largest_Even_Number(string str)
{
    int len ;
    len=str.length() ;
   
    str=sort(str,len) ;
   
    if((str[len-1]-'0')%2==0)
        return str;
       
    int i,pos ;
    for(i=len-1;i>=0;i--)
    {
       if(((str[i])-'0')%2==0)
        {
            pos=i ;
            break ;
        }
    }
   
    int temp ;
    for(i=pos;i<len-1;i++)
    {
        temp=str[i] ;
        str[i]=str[i+1] ;
        str[i+1]=temp ;
    }
   
    return str ;
}

string sort(string str,int no)
{
    int i,j;
    char temp ;
   
    for(i=no-1;i>0;i--)
    {
        for(j=no-1;j>0;j--)
        {
            if(str[j]>str[j-1])
            {
                temp=str[j] ;
                str[j]=str[j-1] ;
                str[j-1]=temp ;
            }
        }
    }
    return str ;
}

// we can use better sorting algo

---------------------------------------------------------------------------------
USING STL Library
---------------------------------------------------------------------------------

#include<iostream>
using namespace std;
#include <string>
#include <stdlib.h>
#include <algorithm>
string Largest_Even_Number(string) ;
bool wayToSort(int i, int j) { return i > j; }
int main()
 {
int t ;
string str ;
cin>>t ;
while(t--)
{
   cin>>str ;
   str=Largest_Even_Number(str) ;
   cout<<str<<endl ;
}
return 0;
}

string Largest_Even_Number(string str)
{
    int len ;
    len=str.length() ;
   
    std::sort( str.begin(), str.end() ,wayToSort) ;
   
    if((str[len-1]-'0')%2==0)
        return str;
       
    int i,pos ;
    for(i=len-1;i>=0;i--)
    {
       if(((str[i])-'0')%2==0)
        {
            pos=i ;
            break ;
        }
    }
   
    int temp ;
    for(i=pos;i<len-1;i++)
    {
        temp=str[i] ;
        str[i]=str[i+1] ;
        str[i+1]=temp ;
    }
   
    return str ;
}

---------------------------------------------------------------------------------

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