Iterate Vector of Strings Backwards

[stdq]

Hello, everyone. I have a variable called listOfTokens, of type std::vector< std::string >, and I am trying to iterate through the elements backwards with the following code:

std::vector< std::string >::iterator it;
std::string currentToken;
 
for ( it = listOfTokens.end() - 1; it != listOfTokens.begin() - 1 ; it-- ){
currentToken = *it;
//...
}

However, I'm getting a runtime error. What am I doing wrong? Thaks in advance.

[Banfa]

Your using a forward iterator and calling the forward begin and end methods, if your code worked you would not include the first item in the vector in your loop.

Try using a reverse iterator with reverse begin and end

std::vector<std::string>::reverse_iterator it;
std::string currentToken;
 
for ( it = listOfTokens.rbegin(); it != listOfTokens.rend(); ++it ){
  currentToken = *it;
  //...
}

[stdq]

Thank you! I did that, but I'm still getting a runtime error. I guess the problem lies somewhere else in my program. Thanks, though!

[Banfa]

Try runni9ng you program in a symbolic debugger, like gdb or debug mode of MSVC++, it should stop when you get the error and allow you to examine the call stack which might indicate what the problem is.