编辑代码

#import <Foundation/Foundation.h>
int main(int argc, char* argv[]) {
    NSString * str=@"Hello world!    - objc.jsrun.net";
    printf("%s",[str UTF8String]);
    NSLog(@"%d", [[NSDate date] timeIntervalSince1970]*1000);
    printf("%$", [[NSDate date] timeIntervalSince1970]*1000);
    return 0;
}