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<SCRIPT LANGUAGE="JavaScript">* n) z, j. ~ ?
<!-- Begin
) t* C/ E/ O P6 Jfunction calculate(form) {
9 Q/ }( N" Q# L6 U) N2 W5 Lvar num=parseInt(form.number.value);
& D5 `5 k% n. K4 m7 tif (isNaN(num) || num < 0) {. o8 N# ]' p# Q( z
form.result.value=(form.number.value + " is not a valid number! Try again!");+ [( H2 R* `7 N- Z" K. U
}
1 P3 Y" X4 i4 h" H7 f. c/ dif (num == 1 || num == 2) {
* m' V+ z# h I f6 ]form.result.value=(num + " is prime!");
5 p& B* s/ s2 }3 b( q6 n9 j} O% i: c7 e* k' G
for (var i=2;i<num;i++) {
/ G( \) ^ A8 Hif (num % i == 0) {" [/ V2 h2 S9 G* S& l% f- g
var prime="yes";
7 T k' ^9 Y6 P6 r" J- uform.result.value=(num + "不是素数,它能被" + i + "整除.");
- U6 }( x! G8 K8 ibreak;$ f: t6 T: m1 q8 ?
}0 v. c O" A+ S2 J( k1 c! O, k1 Z
if (num % i != 0) var prime="no";: `, T* q& j! `. ~& s
}
1 P9 b7 [( M, O vif (prime == "no") form.result.value=(num + "是素数");
+ q l; t. `4 d} , {" e2 q# D) a- O& f
// End -->) j& z* X! z7 r3 q
</SCRIPT>
7 @' z4 }+ F( ~! b" W<form name=form>5 b- K, n) J; Y8 Z1 B8 x& a6 `
<h2>素数检测</h2><p>& z, P, s. ~* b7 L7 G! C+ p" [+ N
请输入一个数:<br>( l) h! C4 x- D& n% ~! K# z7 l/ I
<input type=text name=number size=7>
$ V6 y0 Q% b! U8 m7 q! i% y5 y<input type=button value="Calculate" onClick="calculate(this.form)">* i ?- q; n! @5 M) p8 \
< >
% E; n8 v& E, u2 H2 y8 D8 M<input type=text name=result size=45 value="">
% O5 u) ~) j C! t4 _% i</form> 一段检测素数的JS代码实例! |