Reverse String in Objective-C

Reverse String

in Objective-C

Welcome to the Reverse String in Objective-C page! Here, you'll find the source code for this program as well as a description of how the program works.

Current Solution

#import <Foundation/Foundation.h>

@interface NSString (Reversal)
@property(nonatomic, readonly) NSString* reversed;
@end

@implementation NSString (Reversal)

- (NSString*)reversed {
    NSUInteger len = self.length;
    if (len < 2) return self;

    unichar buffer[len];
    [self getCharacters:buffer range:NSMakeRange(0, len)];

    NSUInteger i = 0;
    NSUInteger j = len - 1;

    while (i < j) {
        unichar tmp = buffer[i];
        buffer[i++] = buffer[j];
        buffer[j--] = tmp;
    }

    return [NSString stringWithCharacters:buffer length:len];
}

@end

int main(int argc, const char* argv[]) {
    @autoreleasepool {
        NSString* input = argc > 1 ? @(argv[1]) : nil;
        NSString* output = input.reversed;
        puts(output.UTF8String);
    }
    return 0;
}

Reverse String in Objective-C was written by:

• Tim Lange
• Ștefan-Iulian Alecu

If you see anything you'd like to change or update, please consider contributing.

How to Implement the Solution

No 'How to Implement the Solution' section available. Please consider contributing.

How to Run the Solution

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