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<SCRIPT LANGUAGE="JavaScript">
- v" f' t* {* o+ C$ r1 k<!-- Begin' \/ D0 u- C$ B) L" v A
function calculate(form) {8 c( `2 Y8 E, k
var num=parseInt(form.number.value);+ \, Z- ~$ a' A4 c6 x3 m
if (isNaN(num) || num < 0) {
6 r! t) J$ \+ Y$ uform.result.value=(form.number.value + " is not a valid number! Try again!");& N( X% h; Y# h% z. N* _
}. ~( K. x7 Y# M @7 U1 B- x/ A
if (num == 1 || num == 2) {- L4 e" G' Z. _ z4 `4 a' c: c
form.result.value=(num + " is prime!");* Q" _! Z; A: U( F
}$ C' E; s7 v9 H
for (var i=2;i<num;i++) {
1 Y; m0 T% j% E/ f/ P9 j; uif (num % i == 0) {3 k- b ?; ?! [* ~* F
var prime="yes";# c9 ?+ a0 [$ k8 z
form.result.value=(num + "不是素数,它能被" + i + "整除.");
8 A, C5 L" o7 c* u: N4 @1 h9 v, t2 {break;6 s$ w. q+ o; h; W) j# k5 D- Q! r. p
}
" D9 G$ \9 g# i7 A% t0 xif (num % i != 0) var prime="no";
$ P7 ?. q7 F. C8 ^4 u( m}' M0 ^, C- Y- J/ c4 x7 n
if (prime == "no") form.result.value=(num + "是素数");- g2 i8 X3 K' v2 J, l! b8 M
} ; T" Y i! X. X' P" V/ M8 T
// End -->
. s* O4 {9 [! X6 K4 Z5 S! J3 [</SCRIPT>
- W) O) Y; G, b7 ^! N3 J<form name=form>5 b# e) }3 `8 J0 o, z' `
<h2>素数检测</h2><p>; \: l3 g& `0 x
请输入一个数:<br>
8 R, o# @$ h6 s9 s D) y# K<input type=text name=number size=7>
/ D' E5 f# p) g2 d! C* O% D+ c<input type=button value="Calculate" onClick="calculate(this.form)">
5 E# ?; b" N# @( }! H7 T) h C< >. W, f% C3 i& B( [2 d
<input type=text name=result size=45 value="">+ u$ l/ P0 _; b: D3 v3 K0 ]$ M
</form> 一段检测素数的JS代码实例! |