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<SCRIPT LANGUAGE="JavaScript">$ t# X" }1 f) `1 L* l. H8 |5 O1 R' T
<!-- Begin5 m( K! f( E- n9 C
function calculate(form) {! q: v, c4 P& n6 L0 y# w- X
var num=parseInt(form.number.value);
2 d- T" [- _5 c6 T9 q3 _0 pif (isNaN(num) || num < 0) {
6 S' y4 O M* O7 ], v" v) g. ^: ?form.result.value=(form.number.value + " is not a valid number! Try again!");
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if (num == 1 || num == 2) {
6 Z; ]; H. n, F |1 t7 b# H/ Sform.result.value=(num + " is prime!"); }$ v1 t/ B) o; n/ d
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for (var i=2;i<num;i++) {
" N7 z6 {" n/ P& C; ?3 lif (num % i == 0) {
4 d+ b: V- O' |0 D0 y2 r/ u- N1 mvar prime="yes";' L0 w. M' X! N
form.result.value=(num + "不是素数,它能被" + i + "整除.");
& g" L9 ]* d; r8 p$ m$ T1 zbreak;! k5 k+ a* w' e% w
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if (num % i != 0) var prime="no";
$ a- x% @& |" |3 b2 h1 f1 d3 n0 ^}
, L3 G6 L8 ]: A' uif (prime == "no") form.result.value=(num + "是素数");
& q' h3 T2 w" {$ ^, h}
( `1 X& f ]8 U4 ~5 \ {9 L' C// End -->
! D$ g$ s# j/ V</SCRIPT>
, H3 p8 m: S) w" J* {$ p<form name=form>7 T3 \/ W* j. X( v' C+ J0 m
<h2>素数检测</h2><p>3 H7 z0 N, l5 E" G* H3 l
请输入一个数:<br>
( z& y3 L# k. c5 v3 `. z<input type=text name=number size=7>
0 V* {8 f3 E r# F! [& s<input type=button value="Calculate" onClick="calculate(this.form)">/ _4 F; p/ m/ V4 u; F* r9 e* \
< >
. K% z, K2 F8 F1 S; ]) f+ j<input type=text name=result size=45 value="">
% K. h3 p& m: H8 d& f6 ~$ c</form> 一段检测素数的JS代码实例! |