鉴于用户输入应介于1和1000之间,我正在尝试使用1-1000的(已排序)整数数组的二进制搜索来输出以下内容:
我只想要输出 - 忽略格式。现在,代码:
const testButton = document.getElementById("test");
testButton.addEventListener('click', () => {
myArray = new Array(1000);
for (i = 0; i < 1000; i++) {
myArray[i] = i + 1;
//just for visual aid, not to be actual part of final output
document.getElementById("boop").innerHTML = myArray;
document.getElementById("boop").innerHTML += `<p>${myArray[myArray.length -1]}</p>`;
}
var userInput = parseInt(document.getElementById("input").value);
let min = myArray[0];
let max = myArray[myArray.length - 1];
if (userInput < 1 || userInput > 1000) {
document.getElementById("boop").innerHTML += "That's not between 1 and 1000.";
} else {
while (min < max) {
userInput = parseInt(document.getElementById("input").value);
let min = myArray[0];
let max = myArray[myArray.length - 1];
let mid = myArray[myArray.length - 1];
mid = parseInt(Math.floor(mid / 2));
let count = 0;
if (userInput == mid) {
count++;
document.getElementById("boop").innerHTML += `<p>Guessed ${mid} and got it. Took me ${count} tries.</p>`;
} else if (userInput > mid) {
count++;
document.getElementById("boop").innerHTML += `<p>Guessed ${mid}. Too low.</p>`;
min = mid + 1;
mid = parseInt(Math.floor(mid + (mid / 2)));
} else {
count++;
document.getElementById("boop").innerHTML += `<p>Guessed ${mid}. Too high.</p>`;
max = mid - 1;
mid = parseInt(Math.floor(mid / 2));
}
}
}
});
<html>
<head>
</head>
<body>
<input type="text" id="input">
<button id="test">
Start Game
</button>
<p id="boop">
</p>
</body>
</html>
如果你想搞砸我的JSfiddle,enter link description here
我在运行它时没有收到任何控制台错误,但它似乎是一个无限循环,因为我的浏览器挂起。我看过类似的问题,我能找到的最相似的是:enter link description here但是它使用的是Java,我还没有学过Java(一般来说编程还很新),所以它有点令人困惑,但我相信它是类似的概念。
提前感谢您提供的任何帮助!
我更新了JSfiddle https://jsfiddle.net/y4ta13es/
无限循环是因为while条件永远不会退出,因为条件总是被评估为真。
大多数代码都是正确的,有一些小的逻辑缺陷,比如你在while循环中定义变量。您应该在其他地方声明它们,永远不会更新这些值。
这是片段
while (min < max) {
index = parseInt((max+min)/2);
let mid = myArray[index];
if (userInput == mid) {
count++;
document.getElementById("boop").innerHTML += `<p>Guessed ${mid} and got it. Took me ${count} tries.</p>`;
break;
} else if (userInput > mid) {
min = index;
count++;
document.getElementById("boop").innerHTML += `<p>Guessed ${mid}. Too low.</p>`;
} else {
max = index;
count++;
document.getElementById("boop").innerHTML += `<p>Guessed ${mid}. Too high.</p>`;
}
}
在while循环中,每次都重置为启动条件。所以基本上它每次都在不断地猜测500。
while (min < max) {
userInput = parseInt(document.getElementById("input").value);
let min = myArray[0];
let max = myArray[myArray.length - 1];
每次while循环执行时,最后两行将其重置为初始条件(所以你是对的,它处于无限循环中)。它将其设置为根据猜测更改最大值或最小值,然后在下次执行时将其重置(为1和1000)。