If I wanted to concatenate an integer with a string, what would the proper syntax?

For a comp sci class, I'm working on my 4th assignment, and I forget how to do this (i'm not asking for you to do my assignment..i just would like some help because I'm stuck. I'm not a C++ programmer. I just know basic C++.)

This is the line I have:
orderArray[x] = lbsPeanuts + " Pounds of Peanuts";

It's giving me compile errors and it is trying to add instead of concatenating lbsPeanuts to " Pounds of Peanuts".

Anyone know how to do this? Thanks.