r/dailyprogrammer Challenge #119 [Easy] Change Calculator

main.m

//
//  main.m
//  ChangeCalculator
//
//  Created by Michael Deeb on 3/10/13.
//  Copyright (c) 2013 Michael Deeb. All rights reserved.
//

#import <Foundation/Foundation.h>


int main(int argc, const char * argv[])
{
    @autoreleasepool {
        // Values of coins.
        NSDecimalNumber *QUARTER = [NSDecimalNumber decimalNumberWithDecimal:[[NSNumber numberWithFloat:0.25] decimalValue]];
        NSDecimalNumber *DIME = [NSDecimalNumber decimalNumberWithDecimal:[[NSNumber numberWithFloat:0.10] decimalValue]];
        NSDecimalNumber *NICKLE = [NSDecimalNumber decimalNumberWithDecimal:[[NSNumber numberWithFloat:0.05] decimalValue]];
        NSDecimalNumber *PENNY = [NSDecimalNumber decimalNumberWithDecimal:[[NSNumber numberWithFloat:0.01] decimalValue]];
        
        // Look for the input file.
        NSString *path = [[NSBundle mainBundle] bundlePath];
        NSString *filePath = [path stringByAppendingPathComponent:@"file.in"];
        NSString *fileContents = [NSString stringWithContentsOfFile:filePath encoding:NSUTF8StringEncoding error:nil];
        
        // Let's put that big string into an array.
        NSArray *lines = [fileContents componentsSeparatedByString:@"\n"];
        
        // Decimal formatting stuff
        NSNumberFormatter *numFormatter = [[NSNumberFormatter alloc] init];
        [numFormatter setMaximumFractionDigits:2];
        // Round up if thousandths place >= 5, else round down (typical POS behavior)
        [numFormatter setRoundingMode: NSNumberFormatterRoundHalfUp];
        
        // Create NSNumber Array
        NSMutableArray *array = [NSMutableArray array];
        for (NSString *numberString in lines) {
            // This seems inefficient.
            NSString *formattedNumber = [NSString stringWithString:[numFormatter stringFromNumber:[NSDecimalNumber decimalNumberWithString:numberString]]];
            [array addObject:[NSDecimalNumber decimalNumberWithString:formattedNumber]];
        }
        
        // Figure out the coinage.
        // Subtracting rather than moding because it seems difficult with NSDecimalNumbers
        for (__strong NSDecimalNumber *coins in array) {
            // Use these to keep track of the amount of each coin
            int quarterCount = 0;
            int dimeCount = 0;
            int nickleCount = 0;
            int pennyCount = 0;
            
            NSLog(@"==========");
            // Prints out formatted number in array array. Would prefer printout of same number unformatted in lines array
            NSLog(@"Change calculation for $%@", coins);
            
            // Check if coins is greater than/equal to quarters
            while([coins compare:QUARTER] == NSOrderedDescending || [coins compare:QUARTER] == NSOrderedSame) {
                coins = [coins decimalNumberBySubtracting:QUARTER];
                quarterCount++;
            }
            
            // Check if coins is greater than/equal to dimes
            while([coins compare:DIME] == NSOrderedDescending || [coins compare:DIME] == NSOrderedSame) {
                coins = [coins decimalNumberBySubtracting:DIME];
                dimeCount++;
            }
            
            // Check if coins is greater than/equal to nickles
            while([coins compare:NICKLE] == NSOrderedDescending || [coins compare:NICKLE] == NSOrderedSame) {
                coins = [coins decimalNumberBySubtracting:NICKLE];
                nickleCount++;
            }
            
            // Check if coins is greater than/equal to pennys
            while([coins compare:PENNY] == NSOrderedDescending || [coins compare:PENNY] == NSOrderedSame) {
                coins = [coins decimalNumberBySubtracting:PENNY];
                pennyCount++;
            }
            
            // Only print out amounts greater than 0
            if(quarterCount > 0)
                NSLog(@"Quarters: %u", quarterCount);
            if(dimeCount > 0)
                NSLog(@"Dimes: %u", dimeCount);
            if(nickleCount > 0)
                NSLog(@"Nickles: %u", nickleCount);
            if(pennyCount > 0)
                NSLog(@"Pennies: %u", pennyCount);
            // In the case of numbers smaller than the hundredths place
            if(quarterCount == 0 && dimeCount == 0 && nickleCount == 0 && pennyCount == 0)
                NSLog(@"This amount of money is too small to make in change with USD.");
            
        }
        
        
    }
    return 0;
}