#include <stdio.h>
#include <math.h>
#define PI 3.141592653589793
void printVector();
int scalar_product();
int factorial();
double my_cos();
int main () {
int u[] = {1,-2,3,-4};
int v[] = {6,7,1,-2};
int w[] = {5,-4,5,7};
int i;
printf ("vector u = ");
printVector (u,4);
printf ("vector v = ");
printVector (v,4);
printf ("vector w = ");
printVector (w,4);
printf ("vector u * v = ");
printf ("%i\n", scalar_product(u,v,4));
printf ("vector u * w = ");
printf ("%i\n", scalar_product(u,w,4));
printf ("vector v * w = ");
printf ("%i\n", scalar_product(v,w,4));
for (i=0;i<7;i++)
printf ("factorial %i = %i\n", i, factorial (i));
for (i=0;i<90;i+=10) {
printf ("my_cos %i = %f\n", i, my_cos (i*PI/180));
printf (" cos %i = %f\n", i, cos (i*PI/180));
}
printf ("end\n");
getchar();
return 0;
}