以下C程序的输出将如何？

Question

What wil be the output? I am confused of the \\\\ . How does it work?

#include <stdio.h>
void main(){
    printf("\\nab");
    printf("\\bsi");
    printf("\\rha");
}

Answer 1

The output will be \\nag\\bsi\\rha . The string "\\\\" converts to literal "\\" .

That is because \\n symbolizes a new line, and there are several other uses for the single char \\ . If it didn't work this way, there would be no way to print the literal \\n .

Answer 2

The answer will be:

\nab\bsi\rha

1 - The three text are printed together because you are using printf without an escape character \\n , if you instead use

...
printf("\\nab\n");
printf("\\bsi\n");
printf("\\rha\n");
...

You will get

\nab
\bsi
\rha

In the first print you are writing \\n and this means a new line, but you are declaring two slashes that indicate to print 'as is' a single slash (in C to print a slash you must be use \\\\ (two) because a single slash is pretended to use for special escape characters like \\n).

Try to execute the your original with it to see the main difference:

#include <stdio.h>

void main()
{
  printf("\nab\n");     /* Note that I am using a escape character \n to make a new line after each print */
  printf("\bsi\n");
  printf("\rha\n");
}

Answer 3

Basically, If this \\ is used before special characters, it is called an escape literal. What this does is, remove the functionality of special characters right infront of it. Ex: Incase you want to print this line in output : Hi this, ", is a quote symbol . You would write it as : printf("Hi this, \\", is a quote");

Similarly for escape sequences such as \\n \\t \\b, to remove the special characte \\ from it would require an escape literal.