<!DOCTYPE html>
<html lang="en">
<head>
<meta charset="UTF-8">
<meta name="viewport" content="width=device-width, initial-scale=1.0">
<title>Yanghui Triangle</title>
</head>
<body>
<script>
function print(v) {
if (typeof v == "number") {
var w = 30;
if (n > 30) w = (n - 30) + 40;
var s = '<span style="padding:4px 2px;display:inline-block;text-align:center;width:' + w + 'px;">' + v + '</span>';
document.write(s);
} else {
document.write(v);
}
}
var n = prompt("请输入幂数：", 9);
n = n - 0;
var t1 = new Date();
var a1 = [1, 1];
var a2 = [1, 1];
print('<div style=text-align:center;">');
for (var i = 0; i <= n; i++) {
for (var j = 1; j < i + 2; j++) {
print(c(i, j));
}
print("<br />");
}
print("</div>");
var t2 = new Date();
print("<p style='text-align:center;'>耗时为（毫秒）：" + (t2 - t1) + "</p>");
function c(x, y) {
if ((y == 1) || (y == x + 1)) return 1;
return c(x - 1, y - 1) + c(x - 1, y);
}
</script>
</body>
</html>
