import java.util.*;
 
public class Main {
    public static int bruteForceCountPairs(int[] arr, int k) {
        int count = 0;
        for (int i = 0; i < arr.length - 1; ++i) {
            for (int j = i + 1; j < arr.length; ++j) {
                if (arr[i] + arr[j] == k) {
                    count++;
                }
            }
        }
        return count;
    }
 
    public static void main(String[] args) {
        int[] arr = {1, 2, 3, 4, 5};
        int k = 6;
        System.out.println("Count of pairs: " + bruteForceCountPairs(arr, k));
    }
}

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