CS193p Fall 2011 Assignment 2--Calculator

gistfile1.m

//Iterates through program, an array of operations and NSNumbers
//Returns human-readable list of numbers and operations in RPN
+ (NSString *)descriptionOfProgram:(id)program
{
    NSString *description = [[NSString alloc] init];
    if ([program isKindOfClass:[NSArray class]]) {
        
        for (int i=0; i<[program count]; i++) {
            
            if ([[program objectAtIndex:i] isKindOfClass:[NSNumber class]]) {
                description = [description stringByAppendingString:[[program objectAtIndex:i] stringValue]];
            } else {
                description = [description stringByAppendingFormat:@"%@",[program objectAtIndex:i]];
            }
            description = [description stringByAppendingString:@" "];
        }
    }
    return description;
}