Question

So I have tried to make this algorithm to work but everytime I run it I get [10,11,7,10,7,5,7,5 ] as my output. The goal was to get results in descending order. Furthermore I do not understand why there are 8 results when my array only contains 6 values. Please Help.. Thank you.
public class searches {

public static void main (String[]args)
{
    int[] array = {10,7,11,5,13,8};
    //ExchangeSort(array);

};

public static void ExchangeSort(int[] num)
{
    int i,j,temp;

    for(i=1;i<num.length-1;i++)
    {
        for(j=i+1;j<num.length;j++)
        {
            if(num[i]<num[j])
            {
                temp = num[i];
                num[i] = num[j];
                num[j] = temp;

                //System.out.println(temp);
            }
        }

    }
};

};

Answer 1

You are ignoring first element in sorting as array index start from 0. Your first loop should start with index 0 and go up to length-1 as:

     for(i=0;i<num.length-1;i++)

Also you need to print the sorted array outside the loops or in the main method using Arrays.toString (no loop required) as:

     // this will print the array elements
     System.out.println("Sorted Array: "+Arrays.toString(num));

and remove the semicolons ; from the end of the methods.

Observatory Note: You method name shouldn’t start with Upper Case letter.

EDIT: Your full corrected code is as below:

public static void main(String[] args) {
    int[] array = {10,7,11,5,13,8};
    exchangeSort(array);
    System.out.println("Sorted Array: "+Arrays.toString(array));
}
public static void exchangeSort(int[] num) {
    int temp;
    for(int i=0;i<num.length-1;i++){
        for(int j=i+1;j<num.length;j++){
            if(num[i]<num[j]){
                temp = num[i];
                num[i] = num[j];
                num[j] = temp;
            }
        }
    }
    System.out.println("Sorted Array: "+Arrays.toString(num));
}