Some characters from the C and C++ character set are not available in all environments. You can enter these characters into a C or C++ source program using a sequence of three characters called a trigraph. The trigraph sequences are:
Trigraph | Single character | Description |
---|---|---|
??= | # | pound sign |
??( | [ | left bracket |
??) | ] | right bracket |
??< | { | left brace |
??> | } | right brace |
??/ | \ | backslash |
??’ | ^ | caret |
??! | | | vertical bar |
??- | ~ | tilde |
The preprocessor replaces trigraph sequences with the corresponding single-character representation. For example,
some_array??(i??) = n;
Represents:
some_array[i] = n;