for 循环案例
for 循环输出直角三角形
流程控制语句是可以嵌套使用的，这里使用嵌套来尝试输出一个直角三角形
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<script>
var row = "";
for (var x = 1; x < 10; x++) {
for (var y = 1; y <= x; y++) {
row = row + "*";
}
console.log(row);
row = "";
}
</script>
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案例代码
for 循环输出金字塔
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<script>
var row = 5;
// 正序输出金字塔
for (var k = 1; k <= row; k++) {
for (var m = 1; m <= row - k; m++) {
document.write("<span style='color: transparent;'>a</span>");
}
for (var n = 1; n <= 2 * k - 1; n++) {
document.write("b");
}
document.write("<br/>");
}
// 倒序输出金字塔
for (var k = 1; k <= row; k++) {
for (m = 1; m <= k - 1; m++) {
document.write("<span style='color: transparent;'>a</span>");
}
for (var n = 1; n <= row * 2 + 1 - k * 2; n++) {
document.write("b");
}
document.write("<br/>");
}
</script>
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案例代码
for 循环输出九九乘法表
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<script>
var row = "";
for (var x = 1; x < 10; x++) {
for (var y = 1; y <= x; y++) {
row += x + "*" + y + "=" + x * y + " ";
}
console.log(row);
row = "";
}
</script>
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案例代码
