console 命令行工具 X clear

console

//计算1+2+3 ... +98+99+100的值
//1 .for循环
function sum1() {
    var result = 0;
    for (var i = 0; i <= 100; i++) {
        result += i;
    }
    return result
}
var s = sum1();
document.write(s + "</br>");

//2. while()循环
function sum2() {
    var result2 = 0;
    var i = 0;
    while (i <= 100) {
        i++;
        result2 += i;
    }
    return result2
}
document.write(sum2() + "</br>");


//    do-while语句
function sum3() {
    var result3 = 0;
    var i = 0;
    do {
        i++;
        result3 += i;
    }
    while (i <= 100);

    return result3
}
document.write(sum3() + "</br>");

<!DOCTYPE html>
<html>
<head>
    <mata charset="utf-8"/>
</head>
<body>
    <script>


    </script>
</body>
</html>