Given an array of words, write a method that determines whether there are any

words in this array that are anagrams of each other.

Sample #1: @[@"bag", @"bat", @"tab"]; // output TRUE

Sample #2: @[@"gab", @"bat", @"laf"]; // output FALSE

#include <Foundation/Foundation.h>

// .h
@interface Solution : NSObject
+ (BOOL) checkAnagram: (NSArray*)words; 
@end

// .m    
@interface Solution ()
@end

@implementation Solution

+ (BOOL) checkAnagram: (NSArray*)words {
    if (words == nil) {
        return NO;
    }
    NSMutableSet* dict = [NSMutableSet set];

    for (NSString* word in words) {
        NSCharacterSet* characterSet = [NSCharacterSet characterSetWithCharactersInString: word];

        if ([dict containsObject: characterSet]) {
            return YES;
        }
        [dict addObject: characterSet];
    }
    return NO;

} 
@end



int main (void) {
    @autoreleasepool {
        NSArray* words = @[@"eat", @"tea", @"ate"];
        NSLog(@"%@", [Solution checkAnagram: words]);
    }
    return 0;
}