In C++, %d means placeholder, % is the guide character, d represents the form of decimal integer, and %d corresponds to the int type.

C++ operator:

Scope operator::

Member access operator.

Pointer to member operator->< /p>

Subscript operator []

Brackets/function operator ()

Increment operator++ unary operator

Decrement operator--

Bitwise negation operator~

Logical NOT operator!

Positive sign +

Negative No.-

Address operator&

Extended information

Usage of "%d" in c++

Example:

intn=10;

charstr[]="abcd";

__int64n64=100000000000;

printf("%d%s% lld",n,str,n64);//Format n, str, n64 into integers, strings, and long integers respectively and print them on the screen

Baidu Encyclopedia—c++ Operator