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<SCRIPT LANGUAGE="JavaScript">' H% a) K3 d% ]" ?9 j
<!-- Begin
- n2 l2 n- m$ M- C1 O+ X; y) _function calculate(form) {
% `. l/ d: |& ]/ y6 A% w, \var num=parseInt(form.number.value);" W2 P* Z f4 d! j! N# B' l0 p4 i: e6 _
if (isNaN(num) || num < 0) {
- n0 H, y H3 e9 W, fform.result.value=(form.number.value + " is not a valid number! Try again!");6 F8 h' D, Q8 y# z V3 U$ g
}
; o2 O3 n- O' o- w* M: \+ k% ~if (num == 1 || num == 2) {% x) U( J& @6 a
form.result.value=(num + " is prime!");
# c% ]2 I, M, J3 i}2 I% g* d3 Y( }/ y/ E R2 x0 H* B
for (var i=2;i<num;i++) {
0 a/ _, n3 @+ f( D0 Q5 gif (num % i == 0) {- J8 A( P0 R# X
var prime="yes";
3 h% p/ t7 T0 p& w5 \+ Fform.result.value=(num + "不是素数,它能被" + i + "整除.");
) u$ g' D' X9 A; X( t" Y' Ibreak;9 r+ K4 g) R. ^
}
0 q' H; c# f1 j" ?if (num % i != 0) var prime="no";' F3 [% C9 `+ b, r& s
}$ K/ B. `1 n( G" y4 V/ N
if (prime == "no") form.result.value=(num + "是素数");1 N5 ^1 ~; d+ S' X o! w
}
0 q0 C" X: R6 A' u+ T) G4 M) n" I3 R// End -->
* v7 A: E! e3 u& \9 h$ X</SCRIPT>3 s1 y! ]% k) D |; k3 f% P
<form name=form>7 k0 }5 i( J% I' m1 z' |
<h2>素数检测</h2><p>, i- `* M4 |) Z1 z2 u; O
请输入一个数:<br>
) e' M$ b7 j q7 p( I" x% W7 s3 q, A<input type=text name=number size=7>
4 \$ v% w' c. l8 p<input type=button value="Calculate" onClick="calculate(this.form)">! S& S6 n: t' d* k( x/ h
< >
! Q$ v$ T/ L) f# [7 L8 h- K<input type=text name=result size=45 value="">
8 z+ z, k1 ^5 j) e</form> 一段检测素数的JS代码实例! |