Sort an array of 0s, 1s and 2s

void sort012(int a[], int n)
    {
        int low=0;
        int mid=0;
        int high=n-1;
        
        while(mid<=high)
        {
            switch(a[mid])          
            {
                case 0:
                    swap(a[low],a[mid]);
                    low++;
                    mid++;
                    break;
                case 1:
                    mid++;
                    break;
                case 2:
                    swap(a[mid],a[high]);
                    high--;
                    break;
            }
        }
    }