Разминка (логическая задачка)

//
//  main.m
//  TestObj-C
//
//  Created by Ilya Lavrenov on 2/25/13.
//  Copyright (c) 2013 Ilya Lavrenov. All rights reserved.
//
 
#import <Foundation/Foundation.h>
 
@interface NumberComparator : NSObject
 
@property (assign, nonatomic, readwrite) NSUInteger firstValue;
@property (assign, nonatomic, readwrite) NSUInteger secondValue;
 
- (id)initWithFirstValue:(NSUInteger)firstArg andSecond:(NSUInteger)secondArg;
+ (id)comparatorWithFirstValue:(NSUInteger)firstArg andSecond:(NSUInteger)secondArg;
 
- (NSInteger)returnPosition;
 
@end
 
@implementation NumberComparator
 
@synthesize firstValue = _firstValue;
@synthesize secondValue = _secondValue;
 
- (id)initWithFirstValue:(NSUInteger)firstArg andSecond:(NSUInteger)secondArg
{
    self = [super init];
    if (self != nil)
    {
        [self setFirstValue:firstArg];
        [self setSecondValue:secondArg];
    }
    return self;
}
 
+ (id)comparatorWithFirstValue:(NSUInteger)firstArg andSecond:(NSUInteger)secondArg
{
    return [[[NumberComparator alloc] initWithFirstValue:firstArg andSecond:secondArg] autorelease];
}
 
- (NSInteger)returnPosition
{
    NSString *firstStringRepr = [NSString stringWithFormat:@"%li", [self firstValue]];
    NSString *secondStringRepr = [NSString stringWithFormat:@"%li", [self secondValue]];
    NSUInteger firstDigits = [firstStringRepr length], secondDigits = [secondStringRepr length];
    NSInteger maxDigits = (firstDigits > secondDigits ? firstDigits : secondDigits) - 1;
    
    if (firstDigits != secondDigits)
        return maxDigits;
    
    NSInteger i = 0;
    BOOL lastComp = [firstStringRepr characterAtIndex:i] == [secondStringRepr characterAtIndex:i];
    while (lastComp && i < maxDigits)
    {
        ++i;
        lastComp = [firstStringRepr characterAtIndex:i] == [secondStringRepr characterAtIndex:i];
    }
    
    return maxDigits - i - (lastComp ? 1 : 0);
}
 
@end
 
int main(int argc, const char * argv[])
{
    @autoreleasepool
    {
        NumberComparator *comparator = [NumberComparator comparatorWithFirstValue:1135 andSecond:2135];
        NSLog(@"%li", [comparator returnPosition]);
    }
    
    return 0;
}