arrays - Counting duplicates in C -

if have array set as:

test[10] = {1,2,1,3,4,5,6,7,8,3,2} 

i want return number 3 since there duplicate 1, duplicate 2 , duplicate 3. how can achieve this? efficiency doesn't matter.

first must sort array easier find duplicates.

here example of sort (bubble sort):

void bubblesort(int numbers[], int array_size) {     int i, j, temp;      (i = (array_size - 1); > 0; i--) {         (j = 1; j <= i; j++) {             if (numbers[j-1] > numbers[j]) {                 temp = numbers[j-1];                 numbers[j-1] = numbers[j];                 numbers[j] = temp;             }         }     } } 

then loop through again , find if values[i] == values[i+1]

note: when create loop make 1 length shorter compensate values[i+1] not go out of bounds.