How can I pair my user's input number in an array whose sum is equal to specified input number?

Question

Here's my hard work code so far, we were asked to do it with GUI. Please help me on what approach should I do next to pair my user's input number in an array whose sum is equal to specified input number?

package josh;


import javax.swing.JOptionPane;

public class Sample {


    public static void main (String args[]) {

        int colInput,rowInput;


        String user_col = JOptionPane.showInputDialog("Enter Column Of Array:");
        colInput =  Integer.parseInt(user_col);


        String user_row = JOptionPane.showInputDialog("Enter Row Of Array:");
        rowInput = Integer.parseInt(user_row);



        int user_value;


        for (int i = 0; i < colInput; i++) {
            for (int j= 0; j < rowInput; j++) {

            String values = JOptionPane.showInputDialog(null, "Enter Value "+(i+1));
             user_value = Integer.parseInt(values);

            final Integer [] value_arr = new Integer [user_value];




                }

            }


        }
}

Here's the sample input and output

Answer 1

I would give you the basic logic that you can use.

// value_arr[] is the array where you have all the elements.
// sum is the number to be paired

Arrays.sort(value_arr);
int i=0,j=value_arr.length-1;

// now value_arr is sorted. we'll use two pointers i & j to move.. i moves in from left side towards centre and j moves from right side towards centre

while(i<j){
     if(value_arr[i]+value_arr[j]>sum){
         j--;
     }
     else if(value_arr[i]+value_arr[j]<sum){
         i++;
     }
     else if(value_arr[i]+value_arr[j]==sum){
         System.out.println(value_arr[i]+"+"+value_arr[j]+"="+sum);
     }
}

Let me know if it helps