Can someone trace the recursive calls of this function. I want to see how it works

1. 12 points | The digital root of a number is obtained by summing up the digits repeatedly until only a single digit remains. For example, the digital root of 7854 is obtained by computing 7+8+5+4 which is 24. Next the digits 2 and 4 are summed to yield 6. Since it is a single digit, this forms the digital root of the given number. Write a recursive function root(int n) that returns the digital root of the argument without making use of any loop constructs ( like for, while etc.) in your function. Partial credit may be given in case your function includes such constructs. root(n) if ( n/10)0) return ( n % 10 ); else return root( n % 10 + root( n /10 ) )