שפת C/מצביעים, מערכים, ופונקציות/תרגילים

unsigned int strlen_without_h(const char *str)
{
  unsigned int i;
  unsigned int len_without_h = 0;
 
  for(i = 0; str[i] != 0; ++i)
    if(str[i] != 'h')
      ++len_without_h;
 
  return len_without_h;
}

void strcpy_without_h(char *dest, const char *src)
{
  unsigned int src_i, dest_i;
 
  for(src_i = 0, dest_i = 0; src[src_i] != 0; ++src_i)		
    if(src[src_i] != 'h')
      dest[dest_i++] = src[src_i];
 
  dest[dest_i++] = 0;  
}

float integrate(float (*f)(float), float a, float b, float delta_x)
{
  float sum = 0;
 
  while(a < b)  
  {
    sum += (*f)(a) * delta_x;
 
    a += delta_x;
  }
 
  return sum;
}

#include <stdio.h>
 
float integrate(float (*f)(float), float a, float b, float delta_x)
{
  float sum = 0;
 
  while(a < b)  
  {
    sum += (*f)(a) * delta_x;
 
    a += delta_x;
  }
 
  return sum;
}
 
float square(float x)
{
  return x * x;
}
 
int main()
{
  const float a = 0;
  const float b = 3;
  const float integral = integrate(square, a, b, 0.001);
 
  printf("The integral of x^2 from %f to %f is ~ %f\n", a, b, integral);
 
  return 0;
}