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tokisakikurumi's solution

to Raindrops in the Objective-C Track

Published at Sep 08 2019 · 0 comments
Instructions
Test suite
Solution

Convert a number to a string, the contents of which depend on the number's factors.

  • If the number has 3 as a factor, output 'Pling'.
  • If the number has 5 as a factor, output 'Plang'.
  • If the number has 7 as a factor, output 'Plong'.
  • If the number does not have 3, 5, or 7 as a factor, just pass the number's digits straight through.

Examples

  • 28's factors are 1, 2, 4, 7, 14, 28.
    • In raindrop-speak, this would be a simple "Plong".
  • 30's factors are 1, 2, 3, 5, 6, 10, 15, 30.
    • In raindrop-speak, this would be a "PlingPlang".
  • 34 has four factors: 1, 2, 17, and 34.
    • In raindrop-speak, this would be "34".

Setup

There are two different methods of getting set up to run the tests with Objective-C:

  • Create an Xcode project with a test target which will run the tests.
  • Use the ruby gem objc as a test runner utility.

Both are described in more detail here: http://exercism.io/languages/objective-c

Submitting Exercises

When submitting an exercise, make sure your solution file is in the same directory as the test code.

The submit command will look something like:

exercism submit <path-to-exercism-workspace>/objective-c/raindrops/Raindrops.m

You can find the Exercism workspace by running exercism debug and looking for the line beginning with Workspace.

Source

A variation on a famous interview question intended to weed out potential candidates. http://jumpstartlab.com

Submitting Incomplete Solutions

It's possible to submit an incomplete solution so you can see how others have completed the exercise.

RaindropsTest.m

#import <XCTest/XCTest.h>

#if __has_include("RaindropsExample.h")
# import "RaindropsExample.h"
# else
# import "Raindrops.h"
#endif

@interface RaindropsTest : XCTestCase

@end

@implementation RaindropsTest

- (void)test1 {
    XCTAssertEqualObjects(@"1", [[[Raindrops alloc] initWithNumber:1] sounds]);
}

- (void)test3 {
    XCTAssertEqualObjects(@"Pling", [[[Raindrops alloc] initWithNumber:3] sounds]);
}

- (void)test5 {
    XCTAssertEqualObjects(@"Plang", [[[Raindrops alloc] initWithNumber:5] sounds]);
}

- (void)test7 {
    XCTAssertEqualObjects(@"Plong", [[[Raindrops alloc] initWithNumber:7] sounds]);
}

- (void)test6 {
    XCTAssertEqualObjects(@"Pling", [[[Raindrops alloc] initWithNumber:6] sounds]);
}

- (void)test9 {
    XCTAssertEqualObjects(@"Pling", [[[Raindrops alloc] initWithNumber:9] sounds]);
}

- (void)test10 {
    XCTAssertEqualObjects(@"Plang", [[[Raindrops alloc] initWithNumber:10] sounds]);
}

- (void)test14 {
    XCTAssertEqualObjects(@"Plong", [[[Raindrops alloc] initWithNumber:14] sounds]);
}

- (void)test15 {
    XCTAssertEqualObjects(@"PlingPlang", [[[Raindrops alloc] initWithNumber:15] sounds]);
}

- (void)test21 {
    XCTAssertEqualObjects(@"PlingPlong", [[[Raindrops alloc] initWithNumber:21] sounds]);
}

- (void)test25 {
    XCTAssertEqualObjects(@"Plang", [[[Raindrops alloc] initWithNumber:25] sounds]);
}

- (void)test35 {
    XCTAssertEqualObjects(@"PlangPlong", [[[Raindrops alloc] initWithNumber:35] sounds]);
}

- (void)test49 {
    XCTAssertEqualObjects(@"Plong", [[[Raindrops alloc] initWithNumber:49] sounds]);
}

- (void)test52 {
    XCTAssertEqualObjects(@"52", [[[Raindrops alloc] initWithNumber:52] sounds]);
}

- (void)test105 {
    XCTAssertEqualObjects(@"PlingPlangPlong", [[[Raindrops alloc] initWithNumber:105] sounds]);
}

- (void)test12121 {
    XCTAssertEqualObjects(@"12121", [[[Raindrops alloc] initWithNumber:12121] sounds]);
}

@end

Raindrops-ObjC/Raindrops-ObjC/Raindrops.h

//
//  Raindrop.h
//  Raindrop-ObjC
//
//  Created by tokisakikurumi on 9/6/19.
//  Copyright © 2019 tokisakikurumi. All rights reserved.
//

@interface Raindrops : NSObject
{
    int number;
}
-(id)initWithNumber:(int)num;
-(NSString *)sounds;
@end

Raindrops-ObjC/Raindrops-ObjC/Raindrops.m

//
//  Raindrops.m
//  Raindrop-ObjC
//
//  Created by tokisakikurumi on 9/6/19.
//  Copyright © 2019 tokisakikurumi. All rights reserved.
//

#import <Foundation/Foundation.h>
#import "Raindrops.h"

@implementation Raindrops
-(id)initWithNumber:(int)num;
{
    number = num;
    return self;
}

-(NSString *)sounds;
{
    NSString * str = @"";
    NSDictionary * dict = @{@"3": @"Pling", @"5": @"Plang", @"7": @"Plong"};
    
    int real_key;
    for(NSString * key in dict)
    {
        id value = dict[key];
        real_key = [key intValue];
        if(number % real_key == 0) {
            str = [NSString stringWithFormat:@"%@%@",str,value];
        }
    }
    
    if([str length] == 0) {
        str = [NSString stringWithFormat:@"%d",number];
    }
    
    return str;
}
@end

int main(int argc, const char * argv[]) {
    @autoreleasepool {
    }
    return 0;
}

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