About trigraph in C/C ++

Let's talk about trigraph in a simple way. In this case, no one can understand trigraph. trigraph is a three-letter word, which is also called a three-hyphen.

Thrgraph came into being in order to take care of the older generation of "proletarian revolutionaries". At that time, their conditions were extremely hard and many keys were missing on the keyboard, the following nine characters cannot be entered:

# \ ^ [] {} | ~

Trigraph appears only after the push.

In other words, each character above is replaced by three other characters. The replacement rules are as follows:

#?? =
\?? /
^ ?? '
[?? (
] ???)
{?? <
} ???>
| ??!
~ ?? -

 

The following is an example of a simple C ++ program:

# Include <iostream>

Using namespace std;

 

Int main (){
Cout <"[]" <endl;

Return 0;
}

When the keyboard didn't have the nine symbols at the time, those programmers wrote:

?? = Include <iostream>

Using namespace std;

 

Int main ()?? <
Cout <"?? (??) "<Endl;

Return 0;
?>

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