Counting items in the array

Question

Hello,
I need a clean way to count the items in an array. I can sort them using :
int []x=new int[150]; I'm using Math.random%10 to get intergers from 0-9;
public static void countItem() // sort items in the array
int min, temp;
for (int i = 0; i < x.length-1; i++)
min = i;
for (int scan = i+1; scan < x.length; scan++)
if (x[scan] < x[min])
min = scan;
// Swap the values
temp = x[min];
x[min] = x;
x[i] = temp;
but once they are sorted I am baffeled on a clean way to count how many of each item are listed.
0001122222222333444444 etc up to 9.
Thanks

Answer 1

but once they are sorted I am baffeled on a clean way to count how many of each item are listed.
0001122222222333444444 etc up to 9I think you're going about this the wrong way. First count, then you've implicitly sorted them (counting sort). public class CountingSort
    public static void main(String[] args)
        int[] arr = {4, 5, 1, 3, 3, 3, 7};
        countSort(arr);
        for (int i = 0; i < arr.length; i++)
            System.out.print(arr[i] + " ");
    static void countSort(int[] arr)
        // Assume all elements of arr are in range 0..9
        // initialise buckets to an array of zeroes - don't rely on this except in Java
        int[] buckets = new int[10];
        for (int i = 0; i < arr.length; i++)
            buckets[arr]++;
// Now reconstruct the array in sorted order
// k is the next element in the array to fill in
int k = 0;
for (int i = 0; i < arr.length; i++)
while (buckets[i]-- > 0)
arr[k++] = i;