#include <stdio.h>

int main(void) {
	int num;
	num = 1;

	printf("I am a simple ");
	printf("computer.\n");
	printf("My favorite number is %d because it is first.\n", num);

	return 0;
}

#include <stdio.h>

void butler(void);                                                              // 函数原型

int main(void) {
	printf("I will summon the butler fucntion.\n");
	butler();                                                                   // 函数调用
	printf("Bring me some tea and writeable DVDs.\n");

	return 0;
}

void butler() {                                                                 // 函数定义
	printf("You rang, sir?\n");
}