os NSNumber NSDate Usage

#import <Foundation/Foundation.h>

int main (int argc, const char * argv[]) {
    
	NSNumber *number = [NSNumber numberWithFloat:3.141592];
	NSLog(@"%d",[number intValue]);
	NSLog(@"%@",[number stringValue]);
	
	//NSDate
	NSLog(@"\n");
	NSLog(@"NSDate usage=====");
	NSDate *date = [NSDate date];
	
	
	//[NSThread sleepUntilDate:[NSDate dateWithTimeIntervalSinceNow:5.0f]];
	//NSLog(@"Slept %f seconds" , [[NSDate date] timeIntervalSinceDate:date]);
	//NSLog(@"%@" ,[date description]);
	
	NSDateFormatter *formatter = [[[NSDateFormatter alloc] init] autorelease];
	formatter.dateFormat = @"/MM/dd/YY HH:mm:ss";
	NSString *timestamp =[formatter stringFromDate:date];
	NSLog(@"%@",timestamp);
	
	//add 100 seconds
	date = [NSDate dateWithTimeIntervalSinceNow:180.0f];
	timestamp = [formatter stringFromDate:date];
	NSLog(@"%@",timestamp);
	
	return 0;
}

Console

2012-08-27 12:45:24.019 object_02[1244:1307] 3
2012-08-27 12:45:24.024 object_02[1244:1307] 3.141592
2012-08-27 12:45:24.026 object_02[1244:1307]
2012-08-27 12:45:24.027 object_02[1244:1307] NSDate usage=====
Running…
2012-08-27 12:45:24.034 object_02[1244:1307] /08/27/12 12:45:24
2012-08-27 12:45:24.036 object_02[1244:1307] /08/27/12 12:48:24