我如何激活我的脚本上的按钮，只点击？

Question

所以我的HTML是：

<!DOCTYPE> 
<head>
    <script src="js/problem1.js"></script>
</head> 
<body> 
    <input id="clickMe" type="button" value="Problem #1" onclick="problem1();" />
    <script src="js/problem1.js"></script>
</body>

我正在运行的脚本是：

var counter = 0   
var total = 0    
var start = prompt("Enter a number here to find the sum of all numbers that are:\n-Between 0 and your number\n-Divisible by 3 or 5")

    function problem1(start) {
        for (counter = 0; counter < start; counter++) {   
            if (counter < start) { 
                if (counter % 3 == 0) {
                    total += counter;
                }
                else if (counter % 5 == 0) {
                    total += counter;
                }
            }
            else if (counter == start) {
                if (counter % 3 == 0) {
                    total += counter;
                    alert(total);
                }
                else if (counter % 5 == 0) {
                    total += counter;
                    alert(total);
                }
                else {
                    alert(total);
                }
            }
        }
    }

我遇到的问题是，现在脚本运行在页面加载上，并立即给我创建start变量的提示。输入整数并单击Ok后，提示窗口消失，什么也不会发生。我意识到脚本是独立运行的，因为它在<head>中被调用。问题是我不知道怎么称呼它，就像按一下按钮。我不想使用JQuery。我见过很多像this one这样的答案，但我正在寻找不需要JQuery的东西。我怎样才能做到这一点？

更新

谢谢你的帮助。现在我偶然发现了第二个问题。我无法让脚本运行或显示警报(不确定是哪个)

Answer 1

将提示放在问题函数中

​

function problem1() {
    var counter = 0   
    var total = 0    
    var start = prompt("Enter a number here to find the sum of all numbers that are:\n-Between 0 and your number\n-Divisible by 3 or 5")

    for (counter = 0; counter < start; counter++) {   
        if (counter < start) { 
            if (counter % 3 == 0) {
                total += counter;
                alert(total);
            }
            else if (counter % 5 == 0) {
                total += counter;
                alert(total);
            }

        }
        else if (counter == start) {
            if (counter % 3 == 0) {
                total += counter;
                alert(total);
            }
            else if (counter % 5 == 0) {
                total += counter;
                alert(total);
            }
            else {
                alert(total);
            }
        }
    }
}

<!DOCTYPE> 
<head>
    <script src="js/problem1.js"></script>
</head> 
<body> 
    <input id="clickMe" type="button" value="Problem #1" onclick="problem1();" />
    <script src="js/problem1.js"></script>
</body>

​