<SCRIPT LANGUAGE="JavaScript"># E* c! o: z3 i7 B1 f, q
<!-- Begin
2 L4 t8 ?8 q1 l) a+ |6 Q: w; Tfunction calculate(form) {
6 A* h; o5 B6 |- e' {var num=parseInt(form.number.value);
, ^ m: O" W$ Eif (isNaN(num) || num < 0) {/ ]# P3 S" f( Q u
form.result.value=(form.number.value + " is not a valid number! Try again!");
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if (num == 1 || num == 2) {+ |4 `) _5 \. l/ Y% b
form.result.value=(num + " is prime!");
: V; q* r4 S) h+ n}/ q: |4 l7 R3 `, y& {
for (var i=2;i<num;i++) {
$ Z+ l5 L m: o/ q: V6 o3 Iif (num % i == 0) {
|* O+ ^, I, Avar prime="yes";2 j) F. K3 A) C; n
form.result.value=(num + "不是素数,它能被" + i + "整除.");
/ }# u4 h2 }* z! ybreak;
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if (num % i != 0) var prime="no";
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if (prime == "no") form.result.value=(num + "是素数");
8 u: {7 x- z7 A} - Q. I) b8 o: a4 ?- Y* s) ^
// End -->
" \1 F3 Q5 ]& B; Q' C9 D4 ^6 d8 t</SCRIPT>
0 b% l! w3 Q) z# e<form name=form>$ H2 r( X$ Q& V B
<h2>素数检测</h2><p>1 G8 ?- h1 {, P% w& q0 b- K3 q
请输入一个数:<br>
, O7 |2 l0 V3 J K<input type=text name=number size=7>0 F- g3 A' S4 v( U- i9 ]/ ^$ B
<input type=button value="Calculate" onClick="calculate(this.form)">
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<input type=text name=result size=45 value="">0 f7 U7 V( @6 Y9 S7 T6 r ?" m
</form> 一段检测素数的JS代码实例! |