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<SCRIPT LANGUAGE="JavaScript">
. V' Q4 n+ U* B& B4 J<!-- Begin& |) x2 f; u$ k0 I' J6 a
function calculate(form) {
H& `/ A, z: |6 B. Vvar num=parseInt(form.number.value);
5 {0 d% I! H |1 _7 h3 ~if (isNaN(num) || num < 0) {5 o9 F: W# j7 h; i, L( c3 `9 S
form.result.value=(form.number.value + " is not a valid number! Try again!");
5 o8 u5 j" e5 z0 h! B% V2 W; x" [- b}
- C9 A4 f& m, n$ D) v8 h9 Nif (num == 1 || num == 2) {
4 F9 E/ p3 ?' S) I' j: Y. {1 |form.result.value=(num + " is prime!");1 J2 ^. ~+ r0 S
}& d. ]+ z7 B1 D3 R' g5 v h3 L! E: H# l
for (var i=2;i<num;i++) {) }/ z' |2 w5 r/ \: m3 p
if (num % i == 0) {" g" O* ^" H3 m+ O8 |4 _4 X1 N$ o
var prime="yes";; f0 K% ~* B; A! } s
form.result.value=(num + "不是素数,它能被" + i + "整除.");
# ~, ?& A( U! u/ O+ }( X! rbreak;* Z5 M( {5 |( Z. H8 G, b3 W8 q- e2 h/ \
}
$ b6 X T; X# u6 O( |if (num % i != 0) var prime="no";
' S0 _6 \' H7 t}
) k: I8 S! M8 ]' i. C' i6 }7 Gif (prime == "no") form.result.value=(num + "是素数");
& f5 \$ z' |' c* ^% k# L}
0 q" q3 f' j, ]// End -->% f" A6 V& O" ~
</SCRIPT>
. V4 g, p& O9 o6 U @0 U<form name=form>0 G' b# N C' v: o% I( M- T) \
<h2>素数检测</h2><p>5 A) ~: x. W9 N
请输入一个数:<br>1 E7 k7 T( K1 r2 t! z4 ^
<input type=text name=number size=7>
7 o$ ]$ o0 L/ J4 ~<input type=button value="Calculate" onClick="calculate(this.form)">
6 V3 B8 l' r2 y< >
* Y, x: g; v0 [7 h# l<input type=text name=result size=45 value="">
5 L9 m; x0 s& n3 [3 |</form> 一段检测素数的JS代码实例! |