Question

Im trying to compare these two chars but on win 32 Visual Studio 2008:

if(mychar1 ==  'ä'  || mychar2 == 'Ä')

Erromess:

Debug Assertion Failed!

File:f\dd\vctools\crt_bld\self_x86\crt\src\xstring
Line 1575

Expression: string subscript out of range

Answer 1

Works on my machine:

#include <iostream>

int main()
{
    char mychar1, mychar2;
    std::cin >> mychar1 >> mychar2;
    if(!std::cin)
        return 2;
    if(mychar1 ==  'ä' || mychar2 == 'Ä' )
       return 1;
    std::cout << "No!\n";
    return 0;
}

Note that the error you quote (“string subscript out of range”) implies that you try to access a character in a string at an invalid index. Something like my_str.at(10) (or, in a Debug build, my_str[10]), where my_str only has 10 characters. Since the code you showed doesn’t access characters in strings, the error is in code you don’t show.

Edit: The code you showed in a comment to your question does access characters in a string using operator[](). When you do string2[0], have you checked that the string isn’t empty?