--Scanf little knowledge about the C language () function

Little knowledge of the C language - scanf()function

scanf()Function:

Specified format input from the standard input device. Where: standard input device refers to an "embedded input devices (such as: keyboards)" (personal opinion).

scanf()Prototype:

Scanf int (const char * the restrict the format, ...);
(when using this function call header <stdio.h>)

scanf()Idiom:

• Use one: enter a single character / number:

#include <stdio.h>

int main()
{
	int n;			//定义一个整型数据n
	char ch;		//定义一个字符数据ch
	printf("Please input a number:");
	scanf("%d",&n);			//输入一个数字
	printf("\n You input number is %d\n",n);

	printf("Please input a character");
	scanf("%c",&ch);		//输入一个字符
	printf("\n You input character is %c\n",ch);

	return 0;
}

• Usage of Two: enter multiple characters / numbers:

#include <stdio.h>

int main()
{
	int n1,n2,n3;
	char ch1,ch2,ch3;
	printf("Please input a number:");
	scanf("%d %d %d",&n1,&n2,&n3);			//输入多个数字,输入空格或回车表示单个数字输入结束（回车为截止符）
	printf("\n You input number is %d\n",n);

	printf("Please input a character");
	scanf("%c0%c0%c",&ch1,&ch2,&ch3);		//输入多个字符，输入数字0或者回车表示单个字符输入结束
	printf("\n You input character is %c\n",ch);

	return 0;
}

• Usage three: the output scanf()function return value:

#include <stdio.h>

int main()
{
	int n;
	int ch;
	printf("Please input a number:");
	ch = scanf("%d",&n);
	printf("\n You input number is %d\n SIZE is %d\n",n,ch);	//此处在scanf()函数返回值中有涉及
}

scanf()Function return value:

• The function returns a value of type int.
• If a and b have been successfully read, then the return value is scanf 2;
• If only a read is successful, the return value is 1;
• If a and b are not successfully read, the return value is 0;
• If you encounter an error or encountered end of file, the return value is EOF. end of file or as Ctrl + z Ctrl + d

scanf()Function conversion specifier:

About printf()introduction and function of scanf()the function of conversion and conversion specification modifier in the small knowledge of C language - the printf()function has been described in detail.