1st round Phone Screen

永远自由的心

1. Race condition, read and write lock, semaphone
https://en.wikipedia.org/wiki/Race_condition

+ A3 d8 T5 q) p% Z$ I" U6 C  U2. ARC vs Garbage Collection
https://docs.elementscompiler.com/Concepts/ARCvsGC/
http://programmers.stackexchange ... -reference-counting

3. Abstract Class, Interface
7 q: _3 `4 T" `* x* X9 N$ [/ s/ `https://docs.oracle.com/javase/tutorial/java/IandI/abstract.html

4. Protocol, Interface in Objective C
http://stackoverflow.com/questio ... col-versus-category

5. Write a function that returns 1 when receives 2 and returns 2 when receives 1; No if statements allowed, switch or ?:

. `4 e$ _4 S/ ?#include <stdio.h>
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int functionTest(int argument) {
  int x = argument - 1;
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  return (x ^ 1) + 1;
}

. Z' Z5 _3 P5 o! K( N1 @0 ^" R' f! sint main() {
  printf("should be 2 - %d\n", functionTest(1));
0 I+ X4 ~2 Y6 O9 n( R0 T- n  printf("should be 1 - %d", functionTest(2));
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$ u8 y7 }9 Y& o: m' I  return 0;
}
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xiaobai

感谢永远自由的心分享~~~

Ada.Zhang

感谢永远自由的心分享~~~好人一生平安~~~