#import <stdio.h>
#import <objc/Object.h>
#import <limits.h>
#import <sys/time.h>

@interface Looping : Object {
  int n0;
}
- (id)init;
- (int)calc:(int)n;
@end

@implementation Looping
- (id)init{
  [super init];
  n0 = 0;
  return self;
}
- (int)calc:(int)n {
  int n1 = n0 + (1 - 2*(n%2));
  n0 = n;
  return n1;
}
@end

double gettimeofday_sec()
{
  struct timeval tv;
  gettimeofday(&tv, NULL);
  return tv.tv_sec + (double)tv.tv_usec*1e-6;
}

int main(){
  id o = [[Looping alloc] init];
  int (*calc)(id,SEL,int);
  SEL selector = @selector(calc:);
/*  calc = (int (*)(id,SEL,int))objc_msg_lookup(o, selector); */
  calc = (int (*)(id,SEL,int))[Looping instanceMethodFor:selector];
  unsigned c;
  int n = 1;
  double t1, t2;
  t1 = gettimeofday_sec();
  for(c=0;c<INT_MAX;c++){
    n = calc(o, selector, n);
  }
  t2 = gettimeofday_sec();
  printf("%d\nObjective-C\t%f\n", n, t2 - t1);
  return 0;
}