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EggmanQi's solution

to Acronym in the Objective-C Track

Published at Apr 25 2019 · 0 comments
Instructions
Test suite
Solution

Convert a phrase to its acronym.

Techies love their TLA (Three Letter Acronyms)!

Help generate some jargon by writing a program that converts a long name like Portable Network Graphics to its acronym (PNG).

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/acronym/Acronym.m

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

Source

Julien Vanier https://github.com/monkbroc

Submitting Incomplete Solutions

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

AcronymTest.m

#import <XCTest/XCTest.h>

#if __has_include("AcronymExample.h")
# import "AcronymExample.h"
# else
# import "Acronym.h"
#endif

@interface AcronymTest : XCTestCase

@end

@implementation AcronymTest

- (void)testAcronymAbbreviateTest1 {
    XCTAssertEqualObjects(@"PNG", [Acronym abbreviate:@"Portable Network Graphics"]);
}

- (void)testAcronymAbbreviateTest2 {
    XCTAssertEqualObjects(@"ROR", [Acronym abbreviate:@"Ruby on Rails"]);
}

- (void)testAcronymAbbreviateTest3 {
    XCTAssertEqualObjects(@"HTML", [Acronym abbreviate:@"HyperText Markup Language"]);
}

- (void)testAcronymAbbreviateTest4 {
    XCTAssertEqualObjects(@"FIFO", [Acronym abbreviate:@"First In, First Out"]);
}

- (void)testAcronymAbbreviateTest5 {
    XCTAssertEqualObjects(@"PHP", [Acronym abbreviate:@"PHP: Hypertext Preprocessor"]);
}

- (void)testAcronymAbbreviateTest6 {
    XCTAssertEqualObjects(@"CMOS", [Acronym abbreviate:@"Complementary metal-oxide semiconductor"]);
}

@end
//
//  Acronym.m
//  exercismOC
//
//  Created by eggman qi on 2019/4/24.
//  Copyright © 2019 EBrainStudio. All rights reserved.
//

#import "Acronym.h"

@interface Acronym ()

@property (nonatomic, strong) NSPredicate *p_onlyStr;
@property (nonatomic, strong) NSPredicate *p_onlyUpperCaseStr;

@end

@implementation Acronym

+ (NSString *)abbreviate:(NSString *_Nullable)str
{
	Acronym *acronym = [[Acronym alloc] init];
	NSArray *resultArr = [acronym wordsArr:str];
	
	return [resultArr componentsJoinedByString:@""];
}

- (id)init
{
	if (self = [super init]) {
		NSString *regex_1 = @"^[a-zA-Z]*$";
		_p_onlyStr = [NSPredicate predicateWithFormat:@"SELF MATCHES %@", regex_1];
		
		NSString *regex_2 = @"^[A-Z]*$";
		_p_onlyUpperCaseStr = [NSPredicate predicateWithFormat:@"SELF MATCHES %@", regex_2];
	}
	return self;
}

- (NSArray *)wordsArr:(NSString *)str
{
	NSMutableArray *tempArr = [NSMutableArray array];
	
	BOOL isMatch = NO; 
	for (int i=0; i<str.length; i++) {
		NSString *subStr = [str substringWithRange:NSMakeRange(i, 1)];
		if ([self isOnlyStr:subStr]) {
			if (isMatch) {
				if (i>0) {
					NSString *preStr = [str substringWithRange:NSMakeRange(i-1, 1)];
					if ([self isUpperCaseStr:preStr]==NO && 
						[self isUpperCaseStr:subStr]==YES) {
						[tempArr addObject:subStr];
					}
				}
			}else {
				[tempArr addObject:[subStr uppercaseString]];
				isMatch = YES;
			}
		}else {
			isMatch = NO;
		}
	}
	
	return tempArr.copy;
}

- (BOOL)isOnlyStr:(NSString *)str 
{
	return [_p_onlyStr evaluateWithObject:str];
}

- (BOOL)isUpperCaseStr:(NSString *)str
{
	return [_p_onlyUpperCaseStr evaluateWithObject:str];
}

@end

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