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<SCRIPT LANGUAGE="JavaScript">
. m7 C" z. [/ H7 i) o5 y7 O* L! e<!-- Begin& K4 X2 X [4 Z4 m( ]$ a% P; x
function calculate(form) {9 V1 v; ^% f- _: c; g
var num=parseInt(form.number.value);: b1 }( H2 d. s! @
if (isNaN(num) || num < 0) {) G+ B1 G: H7 Q
form.result.value=(form.number.value + " is not a valid number! Try again!");. n7 Z+ ]' ~, x1 \( P
}- }& j- V+ Q* O! z3 ?
if (num == 1 || num == 2) {& T3 j/ q3 u6 d" _$ D+ ~) k
form.result.value=(num + " is prime!");
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for (var i=2;i<num;i++) {
$ V# f; g+ q4 K2 M% b5 mif (num % i == 0) {
, ^) K h' K6 V! r. N! cvar prime="yes";9 q% I0 |! F# f9 J
form.result.value=(num + "不是素数,它能被" + i + "整除.");4 Q4 Z( E" k4 [( C
break;
" s, A: ]3 ~# j0 x}
$ P& H6 L; I. D1 w2 Q. iif (num % i != 0) var prime="no";9 ^( G& N u, R/ K3 }* m
}/ ] w, n. n: [- X- K0 p
if (prime == "no") form.result.value=(num + "是素数");$ y* D! o Q5 u" Z2 e
} 4 s3 ?8 i) \# P5 x# l+ {
// End -->& ^6 K8 c& p# E5 k
</SCRIPT>) i2 b1 ?, v' w: R3 A+ P
<form name=form>
( n' z5 ]" k$ \+ X" N. o<h2>素数检测</h2><p>
' R; Y- c; N# ]* I$ ^7 G% E请输入一个数:<br>% P. P2 ^0 i4 [7 j# N% T: L4 ?7 S
<input type=text name=number size=7>+ X7 d& L2 a9 F4 G
<input type=button value="Calculate" onClick="calculate(this.form)">
9 G, ?# d, i4 F5 Y3 L& R, M( D< >1 _# ?& g8 z7 f5 k" W3 U! J
<input type=text name=result size=45 value="">
9 A! E+ U* w" j9 |</form> 一段检测素数的JS代码实例! |