c++ - no duplicate function for a lottery program -

right im trying make function checks see if user’s selection in array , , if itll tell choose diff number. how can this?

do mean this?

bool checknumberisvalid() {    for(int = 0 ; < array_length; ++i)    {       if(array[i] == user_selection)          return false;    }     return true; } 

that should give clue, @ least.