<!DOCTYPE html>
<html>
<head>
<meta charset="UTF-8">
<title></title>
</head>
<body>
</body>
</html>
<script type="text/javascript">
//循环语句:满足判断条件继续执行循环，不满足判断条件停止执行。
//1.while循环：先判断条件，再执行循环
/*var one = 0;
var two = 0;
while(one <= 20){
two = two + one;
one++;
}
alert(two);*/
//2.do-while循环：循环体内的代码，至少执行一次
/*var one = 0;
var two = 0;
do{
two = two + one;
one++;
}while (two < 30);
alert(one);*/
//for循环
/*var two = 0;
for(var one = 0; one <= 20; one++){
two = two + one;
}
alert(two);*/
//跳转语句
//1.continue(跳过)
for(var i = 1; i <= 10;i++){
if(i == 6){
continue;
}
alert(i);
}
//2.break（结束）
for(var i = 1;i <= 10;i++){
if(i == 6){
break;}
alert(i);
}
//数组
//定义方式
//空数组的定义方式
var attr = new Array();
var attr = [];
var attr =new Array(3);
//有值的数组定义
var attr = new Array("zhangsan","lisi","wangwu");
var attr2 = ["zhangsan","lisi","wangwu"];
alert(attr2.length);
//数组的遍历
//1.for遍历
for(var i = 0;i < attr2.length;i++){
alert(attr2[i]);
}
//2. console.log(attr2);
var attr2 = ["zhangsan","lisi","wangwu"];
0: "zhangsan"
1:"sili"
2:'wangwu'
length:3
//3. for-in 遍历
for(var k in attr2){
alert(attr2[k]);
}
//数组的赋值：
//定义一个空数组，对它进行赋值
var aa = new Array();
aa[0] = "茄子";
aa[1] = "西红柿";
aa[2] = "菜椒";
aa[3] = "黄瓜";
console.log(aa);
//循环赋值
for(var i = 0; i <= 5;i++){
attr[i] = i + 1;
}
attr = [1,2,3,4,5,6];
console.log(attr);
/*小练习题1:1-n求和练习题
var two = 0;
for(var one = parseInt(prompt("请输入一个数值"));one >= 1;one --){
two = two + one;
}
alert(two);*/
//2.输入台阶数，求总得分：
/*var jieShu = parseInt(prompt("请输入您所在的阶数"));
var fen = 0;
if(jieShu <= 49){
for(var n = jieShu;n >=1;n-- ){
fen = fen + n;
}
}else if(jieShu > 49 && jieShu <= 100){
fen = (jieShu - 49) * 10 + 1225;
}else{
fen = "输入错误，请输入一到一百的整数"
}
alert(fen);*/
//3：一张纸厚0.0001米，喜马拉雅山高8848米，叠多少次可以达到？
/*var ci = 0;
for(var zhi = 0.0001;zhi < 8848; zhi *= 2){
ci++;
}
alert(ci + "次");*/
//一张纸厚0.0001米，喜马拉雅山高8848米，叠多少次可以达到？
/*var gao = 0.0001;
var i = 0;
while(gao < 8848){
i++;
gao = gao * 2
}
alert(i);*/
//4.篮球练习题：篮球从100米高度落下，每次重新弹起高度是原先的0.6，落到一米需要多少次？
/*var ci = 0;
for(var zhi = 100;zhi > 1; zhi *= 0.6){
ci++;
}
alert(ci + "次");*/
//5.列出100内的所有偶数
/*for(var one = 0; one <= 100 ;one++){
if(one % 2 == 0){
two = one;
document.write(two + "<br />");
}
}*/
/*6.九九乘法表
for(var x = 1;x <= 9;x++){
for(var y = 1;y <= x;y++){
document.write( x + "*" + y + "=" + x * y+" ");
}
document.write("<br />");
}*/
/*7.100以内与7相关的数
var str ="";
for(var yi = 1; yi <= 100;yi ++){
if(yi % 7 == 0){
str += yi+",";
}else if((yi - 7) % 10 == 0 ){
str += yi+",";
}
else if(yi > 70 && yi < 80){
str += yi+",";
}
}
document.write(str);*/
//8.求100以内的质数
/*for(var n = 2;n <= 100;n++){
var m = 1;
for(var x = 2; x < n;x++){
if(n % x == 0){
m = 0;
}
}
if(m == 1){
console.log(n);
}
}*/
//9.购物卡问题:有一百元购物卡，牙刷单价5元，香皂单价2元；洗发水单价15元，有多少种方法可以把一百元刚好用完？
/*var n = 0;
for(var y = 0;y <= 20;y++){
for(var x = 0;x <=50;x++){
for(var s = 0; s <= 6;s++){
if((5 * y + 2 * x + 15 * s) == 100){
document.write("牙刷：" + y + "支，" + "香皂:" + x + "块，" + "洗发水" + s + "瓶，" + "<br />")
n++;
}
}
}
}
console.log(n);*/
</script>
练习题1：
练习题2：
练习题3：
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练习题7：
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练习题9：
