C language recursive exercises

1. Ball objects like shells can pile up into a pyramid with a shell at the top, which is located on a layer composed of four shells, the four shells are located on a layer consisting of nine shells, and so on. Write a recursive function CannonBall that uses the height of the pyramid as a parameter and returns the number of shells it contains. Functions must be implemented recursively, and iterative structures such as while or for cannot be used.

Int CannonBall (int h) {if (h = 1) return 1; else return CannonBall (h-1) + pow (h, 2);} int main (void) {printf ("% d \ n", CannonBall (4); return 0 ;}

2. Compile an exponential function using C to implement n ^ k

Int RaiseToPower (int n, int k) {if (k = 0) return 1; else return n * RaiseToPower (n, k-1);} int main () {printf ("% d \ n", RaiseToPower (3, 4); return 0 ;}

3. Use the Euclidean formula to write a recursive function gcdm, n), which is used to calculate the maximum Appointment Between m and n.

Int gcd (int m, int n) {if (m % n = 0) return n; else return gcd (n, m % n);} int main () {printf ("% d \ n", gcd (18, 4); return 0 ;}