在Objective C中对2D NSArray进行过滤、分组和划分

NSArray *array = @[@[@1, @2, @3], @[@4, @5, @6], @[@7, @8, @9]];

NSPredicate *predicate = [NSPredicate predicateWithFormat:@"SELF IN %@", @[@2, @5, @8]];
NSArray *filteredArray = [array filteredArrayUsingPredicate:predicate];

NSLog(@"%@", filteredArray);

(
    (
        2
    ),
    (
        5
    ),
    (
        8
    )
)

NSArray *array = @[@[@"Apple", @"Banana"], @[@"Apple", @"Orange"], @[@"Banana", @"Orange"]];

NSArray *groupedArray = [array valueForKeyPath:@"@distinctUnionOfObjects.self"];

NSLog(@"%@", groupedArray);

(
    (
        Apple,
        Banana
    ),
    (
        Apple,
        Orange
    ),
    (
        Banana,
        Orange
    )
)

NSArray *array = @[@[@"A", @"B", @"C"], @[@"D", @"E", @"F"], @[@"G", @"H", @"I"], @[@"J", @"K", @"L"]];

NSRange range = NSMakeRange(1, 2);
NSArray *partitionedArray = [array subarrayWithRange:range];

NSLog(@"%@", partitionedArray);

(
    (
        D,
        E,
        F
    ),
    (
        G,
        H,
        I
    )
)