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<SCRIPT LANGUAGE="JavaScript">: \6 C4 \0 _& w8 S- { H
<!-- Begin
: A& |' i2 s, G+ Ufunction calculate(form) {
" ?1 w! I q4 A# y+ H7 g8 ^var num=parseInt(form.number.value);& J4 V3 }. L( D
if (isNaN(num) || num < 0) {
* E3 _# a' W1 G8 a% R* Aform.result.value=(form.number.value + " is not a valid number! Try again!");1 O' m* y/ y. A
}1 u, ~3 r/ H2 [2 l! a% z5 p$ s' C
if (num == 1 || num == 2) {
# n8 K+ G0 n2 F2 Q: ], _form.result.value=(num + " is prime!");6 j. D3 U7 O3 H2 r' p$ y
} }" d3 w8 o' l2 d! Q( ?
for (var i=2;i<num;i++) {
( z$ }( _: h6 R) c$ s( Q1 f* }if (num % i == 0) {# ]# p0 N2 y. }/ h+ n' H' V7 O& X
var prime="yes"; i k, n# o* L' v
form.result.value=(num + "不是素数,它能被" + i + "整除.");6 J& A. G0 N$ M3 X6 t
break;4 ]& U$ U0 h) J; X
}
* d: h7 b4 Q0 C X+ M* r; p5 c, Uif (num % i != 0) var prime="no";- e9 e# g" {2 z; [1 ^$ W
}
/ g) _# M0 T L( G9 Tif (prime == "no") form.result.value=(num + "是素数");
L% `1 q1 c" r4 \6 l' @. E} - O% k6 T, b4 @- Y7 H6 B! \5 U
// End -->! W& L" A5 [$ g; B& g. U3 H% |. }
</SCRIPT>
8 C( H' Q; e: B! N ^4 c$ }<form name=form>
. k/ h. d' k# a+ @2 e6 f7 m! r<h2>素数检测</h2><p>, s$ L- y( G3 R. f
请输入一个数:<br>. Q8 @! V! {. l$ s9 G& D$ q- t
<input type=text name=number size=7>; R& ^. _& I; \$ d( A0 x$ R3 W n
<input type=button value="Calculate" onClick="calculate(this.form)">
: k6 y) j+ o# \0 J3 `4 t5 t< >
/ s/ L6 h: q5 l$ g& z, a! b<input type=text name=result size=45 value="">/ y/ d9 a! s8 g1 C; ~
</form> 一段检测素数的JS代码实例! |