I'm working on a project that will take in an encoded string and decode it using a variety of string manipulations. For this particular one, every character in the string needs to be subtracted by val, so for example "mt|%st|%gwt|s%ht|" should output to "how now brown cow" using val=5. The problem I'm having is in the line.replace code. I'm getting an invalid conversion from char to const char on the third parameter. Any ideas on what I'm missing? Thanks in advance.