Clear the buffer with getchar (strongly recommended, C language is error prone, typical)

What is a buffer ？

Buffer is also called cache , Is a part of memory , Is the storage space reserved in memory , Used to buffer input or output data . According to its corresponding output device or output device , Divided into input buffer and output buffer .

Why clean up the buffer ？

When we read information on disk , The read data will be put into the buffer first , The computer then reads data from the buffer , When the data in the buffer is read , The computer will repeat the above operations as required , Until the end of user reading . however , When we don't need the contents of the buffer and want to skip it , When reading the next part directly , Can we read it directly ？ Obviously not ！ At this time, we need to clear the buffer ;

How to clean the buffer ？

example ： Judge whether it can operate normally ？

#include<stido.h>
int main()
{
    
	char password[10] = {
    0};
	printf(" Please input a password ：\n");
	scanf("%s",password);// The array name is the address , Remember this 
	printf(" Please confirm the password （Y/N）:");
	int ch = gerchar();//getchar The return type of is int type , If it is set to char type , Possible data loss 
	if(ch == 'Y')
	{
    
		printf(" Confirm success \n");
	}
	else
	{
    
		printf(" Confirmation failed \n");
	}
	return 0;
}

The answer is ： You can't .
                    Why? ？[^1]

[1^]: The picture is taken from xiaoxianying emojil.
Because when you are scanf After entering the password , Your return is also put in the buffer , however scanf Read the contents before entering , But left the carriage return symbol in the buffer , This causes when you getchar（） When , There is something in the buffer , thus getchar（） Directly read the carriage return .
resolvent ：

step ：

getchar();

In this way, a character in the buffer can be cleared , For example, the last question ;
What if I want to clean up a lot of garbage in the buffer zone ？ This time we need to use the cycle .

while(getchar()!='\0');

This cycle is very short and delicate , You analyze it carefully , Will find , Finally, the carriage return is cleared ！
I think , friend , You don't want others to prostitute your article for nothing 【 Manual funny 】.