The C Programming Language (K&R) 01x12—Power Function—Section 1.7

Section 1.7 of “The C Programming Language” by Brian Kernighan and Dennis Ritchie aka K&R introduces user-defined functions. They first example they give is their power function. Time to test out their code.

Sample Code.

I am using Visual C++ 2010 and created the sample code as a console application.

// Function prototype.

int power(int m, int n);

// The standard library includes the system function.

#include <cstdlib>

// Standard I/O library.

#include <cstdio>

int main()

{

     int i;

     printf("K&R Section 1.7 Power Function.\n\n");

     for (i = 0; i < 10; ++i)

           printf("%d %d %d\n", i, power(2,i), power(-3,i));

     // Keep console window open.

     system("pause");

     // Return some value.

     return 0;

} // end main

/* power: raise base to n-th power; n >= 0 */

int power(int base, int n)

{

     int i, p;

     p = 1;

     for (i = 1; i <= n; ++i)

           p = p * base;

     return p;

}

Output.