the left and the right operands have type char. According to the C++ Standard when an additive operator is used "
The usual arithmetic conversions are performed for operands of arithmetic or enumeration type.
That means that input and input are converted to type int and the result has the same type int. There is no such a constructor in class std::string that has one parameter of type int. So the compiler issues the error.
I really appreciate it ;
and forget about the function , it does something important , I just changed it for this forum so that the good people like you don't have problem answering me :))))
Thanks again !