JAVA program to find the maximum number that can be made from an integer array

ALGORITHM:

This problem can be simply solved by changing the comparison criteria of any sorting algorithms.

Comparison should be changed as explained

if the two numbers to be compared are a & b then two numbers should be made tempA and tempB such that:
               tempA = a*10^(number of digits in b)+b
               tempB = b*10^(number of digits in a)+a
if tempA>tempB then a is larger than b and vice versa

Code of the above logic implemented with bubble sort is given below:

CODE:

import java.util.Scanner;

class maxNo{

    static int size(int a){                //simple utility function count no of digits
        int count=0;
        do{
            count++;
            a/=10;
        }while(a!=0);
        return count;
    }
//utility function to implement modified comparison criteria of the sort
    static int[] compare(int[] a,int i,int j){          
        double t1,t2;
        int tmp;
        t1=a[i]*Math.pow(10,size(a[j]))+a[j];
        t2=a[j]*Math.pow(10,size(a[i]))+a[i];
        if(t1<t2){
            tmp=a[i];                //swapping ith and jth elements
            a[i]=a[j];
            a[j]=tmp;
        }
        return a;
    }

    static int[] bubSort(int[] a,int size){         //simple bubble sort with comparison criteria changed
        int i,j;
        for(i=0;i<size-1;i++)
            for(j=0;j<size-i-1;j++)
                a=compare(a,j,j+1);
        return a;
    }

    //driver function
    public static void main(String[] args) {
        int n,i;
        Scanner in = new Scanner(System.in);
        System.out.print("\nEnter size of array:");
        n=in.nextInt();
        int[] ar = new int[n];
        System.out.println("Enter the array:");
        for (i=0;i<n;i++)
            ar[i]=in.nextInt();
        ar=bubSort(ar,n);
        System.out.println("Maximum num made from the array is:");
        for (i=0;i<n;i++)
            System.out.print(ar[i]);
    }
}

OUTPUT:

Enter size of array:5
Enter the array:
1 10 11 100 110
Maximum num made from the array is:
11111010100