2019-05-10 星期五 3

• 什么是黄金分割
  The golden ratio is a special number approximately equal to 1.618,we find the golden ratio when we divide a line into two parts so that :the whole lenght divided by the long part is also equal to the long part divided by the short part.

  
  image.png
  image.png
  

  code:

void caculateGoldenRatio(){
    static double number = 2;
    number = 1 / number + 1;
    printf("%lf\n",number);
    caculateGoldenRatio();
}

参考链接：https://www.mathsisfun.com/numbers/golden-ratio.html

• runtime 调用方法的另一种写法
  原理：拿到imp指针，直接传值调用,等价于 performSeletor

    Class class = NSClassFromString(target);
    SEL selector = NSSelectorFromString(action);
    if ([class respondsToSelector:selector]) {
        void *(*func)(id, SEL) = (void *)[class methodForSelector:selector];
        void *returnValue = func(class,selector);
    }

• 忽略编译器的警告写法

#pragma clang diagnostic push
#pragma clang diagnostic ignored "-Warc-performSelector-leaks"
//write the code here
#pragma clang diagnostic pop

参考链接:https://www.jianshu.com/p/84a934fe6f86