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<SCRIPT LANGUAGE="JavaScript">
, @8 n* i: y @6 Z: g$ I<!-- Begin
U5 { b& [' N; m6 c+ w5 bfunction calculate(form) {: P, k: P2 X' x, B. t) Y% H
var num=parseInt(form.number.value);
# ~5 i5 g: x/ L, V3 Z4 w$ o# L; L3 eif (isNaN(num) || num < 0) {8 N! D" W$ A5 P0 Z# z
form.result.value=(form.number.value + " is not a valid number! Try again!");
: o F7 M8 ?9 g) K) g& k7 G}/ {! [+ t( |- N9 L. G
if (num == 1 || num == 2) {
% j. |: l `9 J" ?: _+ f: Kform.result.value=(num + " is prime!");9 ]6 M1 j* P! k1 ]' q
}* O. S. ]5 `7 s' D
for (var i=2;i<num;i++) { T% k- r# S/ X5 X0 \* _
if (num % i == 0) {
9 j6 o, a: I" e3 qvar prime="yes";8 I' p" E; D. |2 U$ W3 ?/ \1 N4 z
form.result.value=(num + "不是素数,它能被" + i + "整除.");
$ P4 \; J: Z( Abreak;
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if (num % i != 0) var prime="no";
. Z# R o9 j9 W, f}
a8 j7 r( ?% z2 c1 d' Z Oif (prime == "no") form.result.value=(num + "是素数");
: A, R0 }/ u* m& X& D} ' {% w% U! N3 `
// End -->
4 y& Z. e* t* A3 l8 i+ {" M& e, C</SCRIPT>: t. ^3 A2 [* {$ o
<form name=form>; s- ]/ O9 y0 \/ a
<h2>素数检测</h2><p>
H' \" K5 [- C( f+ W请输入一个数:<br>
2 l9 Y h5 ]+ Q' `; J<input type=text name=number size=7>
) K4 f' ^$ [* S/ f# |, C4 t<input type=button value="Calculate" onClick="calculate(this.form)">
* a* i3 R- `7 Q. O7 J- r; O< >
; @0 ~ E I9 u' u5 Z0 G<input type=text name=result size=45 value="">7 c/ d+ M# n" O% F3 O
</form> 一段检测素数的JS代码实例! |