<!DOCTYPE html>
<html>
<head>
<meta charset="UTF-8">
<title></title>
</head>
<body>
<table border="1" id="t1">
</table>
</body>
</html>
<script type="text/javascript">
//1、判断一个数是奇数还是偶数
var num1 = 9
if(!(num1 % 2)){
alert(num1+'是偶数')
}
else{
alert(num1+'是奇数')
}
//2、给一个年份，判断是否是闰年
var year = 2018
if((year%4==0 && year%100!=0)||(year%100 == 0 && year%400==0)){
alert(year+'是闰年')
}
else{
alert(year+'不是闰年')
}
//3、给一个数n，计算n的阶乘
var num2 = 5
var content = 1
for (var i = 1; i<=num2; i++) {
content *= i
}
alert(content)
//4、打印99乘法表
var m1 = 1
var n1 = 1
var table =[]
var content =[]
for (var i = 1; i <= 9; i++) {
content = []
for (var j = 1; j <= i; j++) {
content.push(j,'*',i,'=',j*i)
}
table.push(content.join(' '))
}
for (i = 0; i<table.length; i++) {
console.log(table[i])
}
//5、计算1-1/2+1/3-1/4 … 1/100的和
var sum = 1
for (var bottom = 2; bottom<=100; bottom++) {
if(bottom%2 == 0){
sum -= (1/bottom)
}
else{
sum += (1/bottom)
}
}
console.log(sum)
//6、给一个n，求1!+2!+3!+4!+5!...+n!
var num3 = 5
var sum = 0
var content = 1
for (var i = 1; i<=num3; i++) {
for (var j = i; j <= i; j++) {
content *= i
}
sum += content
}
alert(sum)
//7、找到所有的水仙花数
var a, b, c
for (var i = 100; i <= 999; i++) {
a = Math.floor(i/100)
b = Math.floor((i%100)/10)
c = i%10
if((Math.pow(a,3)+Math.pow(b,3)+Math.pow(c,3))==i){
console.log(i)
}
}
//8、输入三个数，找到其中最大的，用一句话写出来
alert(Math.max(2,6,3))
//9、给一个数组，找到其中最大值和最小值
var arr1 = [1,2,5,9,8,7,4]
var arr2 = arr1.sort()
console.log(arr2[0], arr2[arr2.length-1])
//10、用while打印十行十列表格，表格里面写1-100，并且隔行变色
var a = 0
var i = 1
var str1 = '<tr>'
function creatTable(){
str1 += '<td>'+i+'</td>'
}
for (i=1; i<=100;i++) {
creatTable()
if(i % 10 == 0){
str1 += '</tr>'
if(i == 100){
break
}
str1 += '<tr>'
}
}
document.getElementById('t1').innerHTML=str1
console.log(str1)
//11、自己实现随机 a, b 之间的整型
var a = 10
var b = 100
var c
var m = true
while (m){
c = Math.ceil(Math.random()*100)
if (c >= a && c <= b){
console.log(c)
m = false
}
}
</script>
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//10、用while打印十行十列表格，表格里面写1-100，并且隔行变色
var a = 0
var i = 1
var str1 = '<tr style="background-color: red;" >'
function creatTable(){
str1 += '<td>'+i+'</td>'
}
for (i=1; i<=100;i++) {
creatTable()
if(i % 10 == 0){
str1 += '</tr>'
if(i == 100){
break
}
if(i % 20 == 0){
str1 += '<tr style="background-color: red;">'
}
else{
str1 += '<tr style="background-color: yellow;">'
}
}
}
document.getElementById('t1').innerHTML=str1
console.log(str1)
new10.png
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