循环
<body>
<script>
/*
打印所有水仙花数
for(var i=100;i<1000;i++){
var g,s,b;
g=i%10;
s=~~(i/10)%10;
b=~~(i/100);
if(i==g**3+s**3+b**3){
document.write(i);
}
}
*/
</script>
<script>
/*
循环嵌套
for(var i=0;i<=5;i++){
for(var j=0;j<=5;j++){
document.write('*');
}
document.write('<br>');
}
*/
/*
*****
****
***
**
*
*/
/*
for(var i=1;i<=5;i++){
for(var j=i;j<=5;j++){
document.write('*');
}
document.write('<br>');
}
*/
/*
*
**
***
****
*****
*/
/* for(var i=0;i<=5;i++){
for(var j=0;j<=i-1;j++){
document.write('*');
}
document.write('<br>');
} */
/*
*
* *
* * *
* * * *
* * * * *
*/
/* for(var i=0;i<5;i++){
for(var j=0;j<5-i;j++){
document.write(" ");
}
for(var a=0;a<=i;a++)
{
document.write("* ");
}
document.write("<br>");
} */
/*
* * * * * * * * *
* * * * * * * * *
* * * * * * * * *
* * * * * * * * *
* * * * * * * * *
* * * * * * * * *
*/
/* for(var i=0;i<=5;i++){
for( j=i;j<8;j++){
document.write(" ");
}
for(var b=0;b<=8;b++ ){
document.write("* ");
}
document.write("<br>");
} */
/* for(var i=0;i<=5;i++){
for( j=i;j<8;j++){
document.write(" ");
}
for(var b=0;b<=8;b++ ){
if(i==2&&j==2){
if(b==1|| b==i){
}
}
//document.write("* ");
}
document.write("<br>");
} */
/*
九九乘法表
*/
//外层循环遍历行
/* for(var i=1;i<=9;i++){
//内层循环遍历行
for(var j=1;j<=i;j++){
var a=i*j;
//如果结果是一位数 补空格
if(a<10 &&j>1){
a=a+'  '
}
document.write(j+'*'+i+'='+a+'  ');
}
//换行
document.write('<br>')
} */
/* document.write('<table>');
for( var row=1;row<=9;row++){
document.write('<tr>');
for(var col=1;col<=row;col++){
var res=row*col;
document.write('<td>'+row+'*'+col+'='+res+'</td>');
}
document.write('</tr>')
}
document.write('</table>'); */
/* document.write('<table>')
for(var row=1;row<=9;row++){
document.write('<tr>')
for(var col=1;col<=row;col++){
var res=row*col;
document.write('<td>'+row+'*'+col+'='+res+'</td>');
}
document.write('</tr>')
}
document.write('<table>') */
/*
菱形
*
* *
* * *
* * * *
* * * * *
* * * * * *
* * * * * * *
* * * * * * * *
* * * * * * *
* * * * * *
* * * * *
* * * *
* * *
* *
*
*/
for (var i = 1; i <= 8; i++) {
for (var j = 1; j <= 8 - i; j++) {
document.write(" ");
}
for (var a = 1; a <= i; a++) {
document.write("* ");
}
document.write("<br>");
}
for (var b = 1; b <= 7; b++) {
for (var c = 1; c <= b; c++) {
document.write(" ");
}
for (var d = 1; d <= 8 - b; d++) {
document.write("* ");
}
document.write("<br>");
}
</script>
<script>
/*
空心菱形
*/
/* for(var i=1;i<=8;i++){
for(var j=1;j<=8-i;j++){
document.write(" ");
}
for(var j=1;j<=i;j++)
{
if(j==1 ||j==i){
document.write("* ");
}
else{
document.write(" ");
}
}
document.write("<br>");
}
for(var i=1;i<=7;i++){
for(var j=1;j<=i;j++){
document.write(" ");
}
for(var j=1;j<=8-i;j++)
{
if(j==1 || j==8-i){
document.write("* ");
}
else{
document.write(" ");
}
}
document.write("<br>");
}
*/
for (var i = 1; i <= 8; i++) {
for (var j = 1; j <= 8 - i; j++) {
document.write(" ");
}
for (var a = 1; a <= i; a++) {
if (a == 1 || a == i) {
document.write("* ");
} else {
document.write(" "); //剩余的是空格
}
}
document.write("<br>");
}
for (var b = 1; b <= 7; b++) {
for (var c = 1; c <= b; c++) {
document.write(" ");
}
for (var d = 1; d <= 8 - b; d++) {
if (d == 1 || d == 8 - b) {
document.write("* ");
} else {
document.write(" ");
}
}
document.write("<br>");
}
</script>
</body>

浙公网安备 33010602011771号