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<SCRIPT LANGUAGE="JavaScript">
' ~0 i, r$ R) {' P6 k- S# \7 H<!-- Begin, Y j$ ~% {0 r* A) h/ ]
function calculate(form) {' @, C( B" @+ T0 P- Y6 p
var num=parseInt(form.number.value);
! S& r3 A1 o3 Zif (isNaN(num) || num < 0) {; v: B0 t- u, f; F% H
form.result.value=(form.number.value + " is not a valid number! Try again!");) b7 }3 C. S" L# \
}2 E% b2 q! [1 b" J, X4 v
if (num == 1 || num == 2) {9 p# b h/ D) i) W% p
form.result.value=(num + " is prime!");: l; ]/ Q8 Q& Z. _) R
}
6 H4 \( Z4 _/ C1 Gfor (var i=2;i<num;i++) { j W! E( j6 b- u9 w, S
if (num % i == 0) {
: E! K$ A/ c0 R w) E- Fvar prime="yes";
9 H+ N0 u0 L! W3 O& Lform.result.value=(num + "不是素数,它能被" + i + "整除.");
" x. X, o3 }& H8 \: ?, mbreak;3 z& O) U4 v) m. ?# `4 h
}
" s3 d7 w% s1 Pif (num % i != 0) var prime="no";( J4 M* {* X1 u! ?$ E
}
4 m' L7 k% B- \: I( T( ^" [if (prime == "no") form.result.value=(num + "是素数");" [+ o2 H* Z+ G
}
; f3 i/ T* \ ~9 M) O8 Y// End -->2 _/ M1 d& M. B, K6 `
</SCRIPT>* Z( l& {, ^* Y8 z* _9 z
<form name=form>& k; O: i1 X3 [9 m* z2 [. R
<h2>素数检测</h2><p>
- p4 c g& r. U请输入一个数:<br>- I4 t' n( u8 F `( Q2 F
<input type=text name=number size=7>
' x! q, `9 Q; }* r7 {<input type=button value="Calculate" onClick="calculate(this.form)">
# @/ m6 e1 u- v/ T s6 A5 E< >
, j$ @3 S- p( r0 ?/ x1 S<input type=text name=result size=45 value="">
! f4 m$ u1 o' ?2 u1 G</form> 一段检测素数的JS代码实例! |