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<SCRIPT LANGUAGE="JavaScript">( b% U8 M( ~* }7 s" K
<!-- Begin& ^* W' r7 @8 B- Y0 u$ b
function calculate(form) {
! F& E# o; u" i: w2 D& |" t( }. jvar num=parseInt(form.number.value);
7 K7 J9 y9 v: A) |, G) qif (isNaN(num) || num < 0) {
8 k8 Q9 j- K; S: Pform.result.value=(form.number.value + " is not a valid number! Try again!");
7 ^$ X$ i9 {: w; D) |4 Y}
7 Q' f; s9 ^0 Kif (num == 1 || num == 2) {2 \5 Z& L2 U! h1 b9 q
form.result.value=(num + " is prime!");8 M( S6 C4 C6 i' p- u r; {3 r
}2 r7 E1 [; j# D9 f$ K9 e! w% i4 o
for (var i=2;i<num;i++) {
4 J9 v2 A% Y4 j! lif (num % i == 0) {
% v$ { ]% l6 j& M9 r$ avar prime="yes";/ m- O" {6 |/ x/ `* Q& u
form.result.value=(num + "不是素数,它能被" + i + "整除.");
" \: ]6 x+ O5 f7 ^, o2 [9 Kbreak;
u2 W# x/ ~8 z; l8 v1 Y}. ]: I& `' o3 o. U
if (num % i != 0) var prime="no";
1 x3 J- L; }& e4 ^}
* ~& \9 G7 h) a/ |if (prime == "no") form.result.value=(num + "是素数");+ N, ~+ Z" Q8 Q$ D) q2 r2 W
} / n+ o: H# X& U# A- r; I% Y
// End -->9 n& A- v1 g p0 U! Y
</SCRIPT>
& w. ~3 J. n1 | @. u U; q( n<form name=form>2 _* A J* E" G+ @ K. R S
<h2>素数检测</h2><p>
o; o1 J( q. N1 d+ F2 R请输入一个数:<br>3 T9 B: }8 ]7 d5 O( X0 P% ~$ E
<input type=text name=number size=7>( [# x. Y6 n' _* G
<input type=button value="Calculate" onClick="calculate(this.form)">* i6 {. U2 K; f/ ~/ X- _
< >
2 C3 i. \; t- M5 [" Y6 _/ M<input type=text name=result size=45 value="">6 v' W% o8 _5 ~: j
</form> 一段检测素数的JS代码实例! |