#import <Foundation/NSObject.h>
#import <Foundation/NSSet.h>
#import <Foundation/NSValue.h>
#import <Foundation/NSAutoreleasePool.h>
#import <Foundation/NSString.h>
// Create an integer object #define INTOBJ(v) [NSNumber numberWithInteger: v]
// Add a print method to NSSet with the Printing category
@interface NSSet (Printing); -(void) print; @end
@implementation NSSet (Printing); -(void) print {
printf (“{“); for (NSNumber *element in self)
printf (“ %li “, (long) [element integerValue]); printf (“}\n”);
} @end
int main (int argc, char *argv[]) {
NSAutoreleasePool * pool = [[NSAutoreleasePool alloc] init];
NSMutableSet *set1 = [NSMutableSet setWithObjects: INTOBJ(1), INTOBJ(3), INTOBJ(5), INTOBJ(10), nil];
NSSet *set2 = [NSSet setWithObjects: INTOBJ(-5), INTOBJ(100), INTOBJ(3), INTOBJ(5), nil];
NSSet *set3 = [NSSet setWithObjects: INTOBJ(12), INTOBJ(200), INTOBJ(3), nil];


}
NSLog (@”set1: “); [set1 print]; NSLog (@”set2: “); [set2 print];
// Equality test if ([set1 isEqualToSet: set2] == NO)
NSLog (@”set1 equals set2”); else
NSLog (@”set1 is not equal to set2”);
// Membership test
if ([set1 containsObject: INTOBJ(10)] == YES) NSLog (@”set1 contains 10”);
else NSLog (@”set1 does not contain 10”);
if ([set2 containsObject: INTOBJ(10)] == YES) NSLog (@”set2 contains 10”);
else NSLog (@”set2 does not contain 10”);
// add and remove objects from mutable set set1
[set1 addObject: INTOBJ(4)]; [set1 removeObject: INTOBJ(10)]; NSLog (@”set1 after adding 4 and removing 10: “); [set1 print];
// get intersection of two sets
[set1 intersectSet: set2]; NSLog (@”set1 intersect set2: “); [set1 print];
// union of two sets
[set1 unionSet:set3]; NSLog (@”set1 union set3: “); [set1 print];
[pool drain]; return 0;
Program 15.16 Output
set1: { 3 10 1 5 } set2: { 100 3 -5 5 } set1 is not equal to set2 set1 contains 10 set2 does not contain 10 set1 after adding 4 and removing 10: {3154} set1 intersect set2: {35} set1 union set : { 12 3 5 200 }