Fill in recursive function decreaseFirstDigitint n) which returns the parameter n with only the first digit decrease by 1 and the rest digits remain the same. If the first digit is 1, then it becomes O
Ex:
n= 1234
n = decreaseFirstDigit(n); //no change, n is 234
n= 2
n = decreaseFirstDigit(n); //n becomes 1
n= 5432
n= decreaseFirstDigit(n); //n becomes 4432,
int decreaseFirstDigit(int nX
if (n _________10) return____________
intr sol =_______ (n_________________)
return r _sol ___________________