1 #include<stdio.h> 
 2 main() 
 3 { 
 4   int c;
 5   c=getchar();
 6   while (c !=EOF) 
 7     {
 8       if (c=='\t')
 9     {
10       c='\\';
11       putchar(c);
12       c='t';
13       putchar(c);
14     }
15       if (c=='\b')
16     {
17       c='\\';
18       putchar(c);
19       c='b';
20       putchar(c);
21     }
22       if (c== '\\')
23     {
24       putchar(c);
25       putchar(c);
26     }
27     }
28 }