import java.util.*;
public class DuplicateClass {
public static void main(String[] args) {
int[] values = { 7, 2, 6, 1, 4, 7, 4, 5, 4, 7, 7, 3, 1 };
duplicate(values);
}
public static void duplicate(int numbers[]) {
Arrays.sort(numbers);
int previous = numbers[0] - 1;
int dupCount = 0;
for (int i = 0; i < numbers.length; ++i) {
if (numbers[i] == previous) {
++dupCount;
} else {
previous = numbers[i];
}
}
System.out.println("There were " + dupCount + " duplicates in the array.");
}
}