Write a program which defines a function print_string which has two
parameters: string that is to be printed and pointer to a function which
prints a single character.
Write a main function which calls print_string

洋文不好，看不懂…

#include <stdio.h>

void printf_string(char *sz)
{
  printf(sz);
}

void print_string(char *szbuff, void(*pfun)(char *))
{
  pfun(szbuff);
}

int main()
{
  print_string("hello world", printf_string); 
  return   0;
}