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<SCRIPT LANGUAGE="JavaScript">% C4 x9 U" r' G9 M# @0 H
<!-- Begin
; z" H) m% P- R7 X. b- _, }/ Y: Afunction calculate(form) {
$ x* G8 i2 ?& H: R4 kvar num=parseInt(form.number.value);5 a# P/ P3 B9 I9 a
if (isNaN(num) || num < 0) {
# H( _/ y. B+ e" mform.result.value=(form.number.value + " is not a valid number! Try again!");
' c+ {/ h' P, D8 }}) G) u( H' f7 } @
if (num == 1 || num == 2) {8 c% Q6 X0 }* o, K
form.result.value=(num + " is prime!");. }5 t1 |; g5 |5 X0 w, J6 f
}
6 M6 v+ W+ M5 o3 ]1 Ofor (var i=2;i<num;i++) {
`8 q! I7 ], Y! n( l2 j8 aif (num % i == 0) {
( d' J& t# {! P" _var prime="yes";: A2 ?6 |, ]" j5 o' h; G. i7 s
form.result.value=(num + "不是素数,它能被" + i + "整除.");- p; A1 \8 @: c
break;' Q4 _. J; v3 A9 M0 i; O' Z2 ]5 y: C% w
}
% _& M! P: B. P* |if (num % i != 0) var prime="no";
# {* N( E4 {- c: f3 o3 w* a# X}5 E4 B6 [* e8 a, v; J* D- j
if (prime == "no") form.result.value=(num + "是素数");
& l" g4 f* K: P6 _2 {5 v2 C}
% N! ~3 j/ ]2 O8 u! v: p/ x7 ~4 P// End -->: M( K' G* `/ F$ B. q D! `
</SCRIPT>6 d9 \3 y- H1 O" s# ]8 j* R
<form name=form>: S! ]4 t& j5 p: ^$ f. P) h
<h2>素数检测</h2><p>
+ F0 Z" \& j$ i) b请输入一个数:<br>
+ d' L/ `# y9 N3 d9 v<input type=text name=number size=7>4 Q8 s" m+ t% E1 x
<input type=button value="Calculate" onClick="calculate(this.form)">8 k8 a( h* m- {" h
< >
: F1 T' w. O/ b3 N+ v" D. i<input type=text name=result size=45 value="">5 [: S" D1 m4 W @
</form> 一段检测素数的JS代码实例! |