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<SCRIPT LANGUAGE="JavaScript"># ], s! |+ |; C/ p
<!-- Begin9 k( ~3 m9 g+ V4 `5 S( Z4 a- Y
function calculate(form) {
! }# T4 ^7 g& d K+ S) Qvar num=parseInt(form.number.value);; P$ C0 _2 m* v. S
if (isNaN(num) || num < 0) {/ `3 h3 n! E$ j/ D0 \
form.result.value=(form.number.value + " is not a valid number! Try again!");
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if (num == 1 || num == 2) {6 T* C+ H( E6 S; Y0 \
form.result.value=(num + " is prime!");
& o0 v) X' ?$ k}
6 Q3 n% y* j0 V$ ]/ kfor (var i=2;i<num;i++) { [7 \7 ^; _8 e1 T9 C$ Y! G
if (num % i == 0) {
/ |& h+ q; K- g1 n5 F2 p' ~var prime="yes";5 V/ @$ f: @3 D6 q5 I# n- t
form.result.value=(num + "不是素数,它能被" + i + "整除.");
7 B7 N$ g" Q! Fbreak;
( {; t4 r3 f) B5 c5 }2 w}$ L+ x$ \8 }; A E! s2 N5 t) e7 t
if (num % i != 0) var prime="no";* l2 K+ R, P A' q: f
}
0 t, T, y; C/ Q1 _& l* H0 M" H, Uif (prime == "no") form.result.value=(num + "是素数");
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// End -->
; K5 i |$ [- w7 T" N( a/ T6 o" t% ~</SCRIPT>& ?' V& {! B2 @
<form name=form>% P) A+ v" P$ q" q3 z9 o
<h2>素数检测</h2><p>
; p- Q% D: Y/ u, } U" }/ Z$ `请输入一个数:<br>2 I/ l' K* y7 Z# d
<input type=text name=number size=7>% T" A+ K+ w6 q
<input type=button value="Calculate" onClick="calculate(this.form)">
1 X2 Y7 m' Y' D' b- ~% ]: B+ W< >
8 b8 M5 I/ A0 H% n<input type=text name=result size=45 value="">
^: D+ y) u3 w& u7 x/ L% a</form> 一段检测素数的JS代码实例! |