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<SCRIPT LANGUAGE="JavaScript">
4 q5 r: \3 ^. G& ?<!-- Begin( M. n$ ^' R5 p0 }
function calculate(form) {9 K% ~4 L0 x5 J0 ^( e: Q1 W. z6 {
var num=parseInt(form.number.value);& O* g* G% K0 Y* d2 A( L# f. ?+ \$ k
if (isNaN(num) || num < 0) {: L, a1 @2 ~* V1 G' p6 |
form.result.value=(form.number.value + " is not a valid number! Try again!");
* [, `4 q/ m( Z# ?4 Q; H}
5 x( z2 R: j9 H3 s( lif (num == 1 || num == 2) {$ v& L5 D2 R( i2 m
form.result.value=(num + " is prime!");
4 d0 L6 u% [6 I) f}
& R' C0 Z' R# \( _# d4 A8 w8 i4 _for (var i=2;i<num;i++) {
' r0 R/ h+ l, s4 ~* c4 H P2 T% qif (num % i == 0) {* Q7 Z& \& z" p1 c. z
var prime="yes";1 D/ B7 E$ W$ u
form.result.value=(num + "不是素数,它能被" + i + "整除.");2 Y: `7 D4 g1 P( [
break;
0 [( x, v; s; O}
7 s9 ?6 A0 @, \' g" Y: Pif (num % i != 0) var prime="no";
9 B6 O/ l* i9 R1 N8 o( n}
% I2 L/ d1 V3 E2 Cif (prime == "no") form.result.value=(num + "是素数");: x' T; r7 C W9 y6 ?6 c
} * i; y3 p+ n: G7 I' P
// End -->
' T7 \; f1 K0 D' l# H) |3 Y( j</SCRIPT>
2 t X$ ?( r6 \0 V* F4 O( d<form name=form>8 j8 B" G% B6 g. L3 g
<h2>素数检测</h2><p>
# m7 |( [* _! T7 \# f' c' b) I. o请输入一个数:<br>- Q* m8 t6 R# S7 U& q; a
<input type=text name=number size=7>6 {9 |* ~( e. J
<input type=button value="Calculate" onClick="calculate(this.form)">* T! w1 K) C( c" v- Q
< >
, [9 c& B' s! C+ v7 k! y" @5 g, Z$ D<input type=text name=result size=45 value="">$ E! R5 W* j9 L9 p0 t! D# O
</form> 一段检测素数的JS代码实例! |