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<SCRIPT LANGUAGE="JavaScript">$ J6 ~, H% B. U: c/ P8 R
<!-- Begin
2 D( S" k1 @& S) Bfunction calculate(form) {
7 ^5 S2 D- G+ w' x4 N% cvar num=parseInt(form.number.value);& H% i% p# n7 X$ O2 _, i' ?
if (isNaN(num) || num < 0) {
2 [5 t: ?: l2 R/ m# _( @form.result.value=(form.number.value + " is not a valid number! Try again!");
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if (num == 1 || num == 2) {
5 d. |* x2 q. u# ?) T. xform.result.value=(num + " is prime!");
, o `# M2 h% u, G4 L8 ^. U}
7 N$ b6 G- p! r' n3 Zfor (var i=2;i<num;i++) {
! k9 D8 v6 Y" K: A$ _) c* xif (num % i == 0) {. j7 u8 S( I7 i* g) ]
var prime="yes";7 j9 `$ l" {8 J6 c8 u" @/ H
form.result.value=(num + "不是素数,它能被" + i + "整除.");$ \3 s( D h# b: t6 Q! \% Q8 n
break;$ |' ]0 p0 r! j
}
- J% k3 H% o: M9 O* }if (num % i != 0) var prime="no";
/ o, a( C0 f' {}) Z5 O8 ?0 E! r' Y& o. Z% {8 ]
if (prime == "no") form.result.value=(num + "是素数");
6 [4 p& x1 W: ?9 q: ^5 }}
; z3 i" `: F. o// End -->
# Y- r3 }/ D7 V) D</SCRIPT>1 L% c4 P+ y! A8 O0 B2 U" s( `
<form name=form>
/ S) q& P S2 u1 Z- {3 {! j6 T# i<h2>素数检测</h2><p>
% _ L# z ^2 R6 n请输入一个数:<br>
. N6 _; g( R4 o: V% _& J K) a<input type=text name=number size=7> I& y' ~9 r$ u; u# }1 k3 G/ _
<input type=button value="Calculate" onClick="calculate(this.form)">! G) a# V5 w% n( S
< >- ]. f; @, J, ?9 X6 u1 k* Y
<input type=text name=result size=45 value="">2 P& u5 T. g4 I" b9 ^/ B, E" O4 b
</form> 一段检测素数的JS代码实例! |