1. 编程题
1) 请用js定义一个Animal类,包含属性name以及方法sleep
2) 请定义Person类,继承上面的类,并添加speak方法
function Animal() { this.name = ''; } Animal.prototype.sleep = function () { console.log('sleep...'); }; function Person () {} Person.prototype = new Animal(); Person.prototype.constructor = Person; Person.prototype.speak = function() { console.log('speak...'); };
2. 写一个求平方根的方法,第一个参数x为一个整型的操作数,第二个参数y也为整型,表示允许误差
function mySqrt (x, y) { let result; ... return result; }
满足
x - result * result <= y
请将函数补充完整(不要用Math.sqrt())
function mySqrt (x, y) { let result; let start = 0, end = x, mid; while(true) { mid = (start + end) / 2; if (Math.abs(x - mid * mid) <= y) { result = mid; break; } if (x > mid * mid) { start = mid; } if (x < mid * mid) { end = mid; } } return result; } mySqrt( 100, 0.01 );