模擬實現printf

要求：能完成下列函數的調用

print("sccc d.\n","hello",'b','i','t'，100);
print函數原型：print(char*format, ...) 

printf函數原型：

int printf( const char *format [, argument]... );
printf函數可以這樣用：printf("%s","hello world");
                    printf("%s%c","hello worl",'d');

printf函數的模擬實現需用到函數可變參數

#include <stdio.h>
#include<stdlib.h>
#include<stdarg.h>
void pri(int num)
{
	if (num > 9)
		pri(num / 10);
	printf("%d",num % 10);
}//遞歸打印數字
void print(char *format, ...)
{
	va_list arg;
	va_start(arg, format);//初始化arg指向未知參數列表的第一個參數
	char *address = NULL;
	int num = 0;
	int i = 0;
	while (*format != '\0')
	{
		char tmp = *format;
		switch (tmp)
		{
		case 's':
			address=(char *)va_arg(arg, int);
			while (*address != '\0')
			{
				putchar(*address);
				address++;
			}
			break;//打印字符串
		case 'c':
			putchar(va_arg(arg, char));
			break;//打印字符
		case 'd':
			pri(va_arg(arg, int));
			break;//打印數字
		default:
			putchar(*format);
			break;
		}
		format++;
	}
	va_end(arg);
}

int main()
{
	print("s ccc d.\n", "hello", 'b', 'i', 't',100);
	system("pause");
	return 0;
}

運行結果