Yes. As per the manual page of errno i.e man 3 errno
Valid error numbers are all nonzero; errno is never set to zero by any system call or library function.
For more info regrading different types of errno please have a look on man page of errno.
A list contains a set of numbers, one number presents once and other numbers present even no. of times. Find out the number that occurs once in the list.
I want to count the number of bytes in a stream that contains nulls. I know I can't use strlen() for this, is there an alternative?
char *stream = "\x11\x12\x13\x00\x12\x13\x14\x15";
For example
Input : Binary Tree
A / \ B E / \ \ C D B / \ C D
Output : Yes