I'm new to C++ programming although I'm pretty familiar with programming in general. I have issue relating to strings I've stored. Essentially I have a map defined as follows.

Code:
map<string, string> resources;
I've added a number of elements to it without any problem. Where I run into problems is after retrieving a value and trying to use the string like so.

Code:
string s1(resources["width"]);
string s2("x");
s1 += s2;
cout << s1 << endl;
This is a simplified version of my code but it illustrates the problem. If s1 = "1280" and I concatenate s2 onto it I will get the following output "x280" instead of "1280x".

What am I doing wrong? Thanks.