OC中可变字典和不可变字典

#import <Foundation/Foundation.h>

int main(int argc, const char * argv[])
{
//不可改变字典，创建后不可改变

NSDictionary * dic = [[NSDictionary alloc]initWithObjectsAndKeys:@"jack",@"name",@"18",@"age", nil];
NSLog(@"%@",dic);
NSDictionary * dic1 = @{@"name":@"jack",@"age":@"18"};
NSLog(@"dic1 %@",dic1);

NSNumber * num = [NSNumber numberWithInt:10];
NSArray * array = @[@"one",@"two",@"three"];
NSDictionary * dic2 = @{@"array":array,
@"num":num,
@"dic":dic
};
}

#import <Foundation/Foundation.h>

int main(int argc, const char * argv[])
{
NSMutableDictionary * dic =
[[NSMutableDictionary alloc]
initWithObjectsAndKeys:@"Tom",@"name" ,@"20",@"age",nil];
}