When should I use single quotes and double quotes in C or C++ programming?
Double quotes are for string literals, e.g.:
char str[] = "Hello world";
Single quotes are for single character literals, e.g.:
char c = 'x';
EDIT As David stated in another answer, the type of a character literal is int
.
I was poking around stuff like: int cc = 'cc'; It happens that it's basically a byte-wise copy to an integer. Hence the way to look at it is that 'cc' which is basically 2 c's are copied to lower 2 bytes of the integer cc. If you are looking for a trivia, then
printf("%d %d", 'c', 'cc'); would give:
99 25443
that's because 25443 = 99 + 256*99
So 'cc' is a multi-character constant and not a string.
Cheers
Single quotes are for a single character. Double quotes are for a string (array of characters). You can use single quotes to build up a string one character at a time, if you like.
char myChar = 'A';
char myString[] = "Hello Mum";
char myOtherString[] = { 'H','e','l','l','o','\0' };
Use single quote with single char as:
char ch = 'a';
here 'a'
is a char constant and is equal to the ASCII
value of char a.
Use double quote with strings as:
char str[] = "foo";
here "foo"
is a string literal.
Its okay to use "a"
but its not okay to use 'foo'
Single quotes are denoting a char, double denote a string.
In Java, it is also the same.
In C and in C++ single quotes identify a single character, while double quotes create a string literal. 'a'
is a single a character literal, while "a"
is a string literal containing an 'a'
and a null terminator (that is a 2 char array).
In C++ the type of a character literal is char
, but note that in C, the type of a character literal is int
, that is sizeof 'a'
is 4 in an architecture where ints are 32bit (and CHAR_BIT is 8), while sizeof(char)
is 1 everywhere.