gistfile1.txt

public class Ch5_q7 {
	public static void main(String[] args) {
		int[] mateArray = new int[21];
		int counter = 1, starter = 1;
		mateArray[0] = 0;
 		while (counter < 21) {
			if (starter != dividerSum(starter) && starter == dividerSum(dividerSum(starter))) {
				if  (starter != mateArray[counter-1]) {
				mateArray[counter] = starter;
				mateArray[counter+1] = dividerSum(starter);
				counter += 2;
				}
			}
			starter++;
		}
		for (int i = 1; i < 21; i += 2) {
			System.out.println(mateArray[i] + " and " + mateArray[i + 1] + " are friendly numbers");
		}
	}

	public static int dividerSum(int num1) {
		int num2 = 0;
		for (int index = 1; index < num1; index++) {
			if ((num1 % index) == 0) {
				num2 += index;
			}
		}
		return num2;
	}
}