Even with the fix the program is still broken. If it doesn't crash it may appear to work, because you only print the first character of the name. But you might change showAscii to print it for the whole string, take both firstName and surname and then call the function on those.
char firstName[]="";char surname[]="";
Here you declare two character arrays. You are letting the compiler to deduce the size of the array from the provided string. Since it is empty, the size of both arrays will be 1 character - just enough to store the null-terminator. You can't legally put any more characters in it.
You'll need to declare larger arrays if you want to store anything in it:
char firstName[20];char surname[20];
Of course, the problem won't go away if the user's name happens to be longer than 20 (19) characters. For that reason C++ has a standard string class which takes care of aquiring and managing needed memory automatically and relieves you of most troubles.
Here's your program rewritten to use string:
#include <iostream>#include <string>using namespace std;//don't use global variables unless you really need to//char firstName[]="";//char surname[]="";//int firstNameTotal = 0;//int surnameTotal = 0;void showAscii(const string& input);int main (int argc, char *argv[]){ string firstName; cout<<"Please enter your first name: "; cin>>firstName; cout<<"Your first name is: "<<firstName<<"\n"; showAscii(firstName); return (0);}void showAscii(const string& input){ cout<<"DEBUG: The first character at position [0] is: "<<input[0]<<" and its ASCII value is: "<<int(input[0])<<".\n";}
