What is 'n' doing? (Bubble sort)

[Hashimatsu]

Exactly as the title suggested: what is the 'n' for in this code?

void bubbleSort(int arr[], int n) {    // 'n'
 
      bool swapped = true;
 
      int j = 0;
 
      int tmp;
 
      while (swapped) {
 
            swapped = false;
 
            j++;
 
            for (int i = 0; i < n - j; i++) {    // 'n'
 
                  if (arr[i] > arr[i + 1]) {
 
                        tmp = arr[i];
 
                        arr[i] = arr[i + 1];
 
                        arr[i + 1] = tmp;
 
                        swapped = true;
 
                  }
 
            }
 
      }
 
}

The 'n' is a value passed to the function, but if I don't know what it's doing I don't know what to pass...

Thanks

[Splux]

It is the size of the array.