gistfile1.txt

-(id)initWithTerms:(NSArray*)ts{ // 5 points
    // REQUIRES: "ts" satisfies clauses given in the representation invariant
    // EFFECTS: constructs a new polynomial using "ts" as part of the representation.
    //            the method does not make a copy of "ts". remember to call checkRep to check for representation invariant
    if (self = [super init]) {
        terms = [ts sortedArrayUsingComparator:^NSComparisonResult(id a, id b) {
            // RatTerm has a property expt that is an int
            int first = [(RatTerm*)a expt];
            int second = [(RatTerm*)b expt];
            
            if (first > second) return NSOrderedAscending;
            else if (first < second) return NSOrderedDescending;
            else return NSOrderedSame;
        }];
        [self checkRep];
        return self;
    } else return nil;
    
    return self;
}

// Error message [__NSArrayI objCType]: unrecognized selector sent to instance 0x102f92b70