Base code for the third CRM Science Lab Coat Challenge

LabCoatChallenge_IncrementLetter.cls

//  Start with this
public String getResult(string letter, integer step) {
    String result;
    
    //  Your code here!  
    /*  Increment/Shift the provided letter by the step provided.
        IE:  getResult('A', 1) should yield "B" and getResult('A',2) should yield "C" */
    
    return result;
}

//  Confirm your results
system.assertEquals('B', getResult('A',1));
system.assertEquals('C', getResult('A',2));
system.assertEquals('A', getResult('Z',1));