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<title>JS基础</title>
<script type="text/javascript">
var a,b,sum;
var a = 5;
var b = 100%7;
sum = a > b && a*b > 0 ;
document.write( "我认为 a 的值是:" + 5 + " b的值是:" + 2 + "sum 的值是:" + true +"<br/>");
document.write( "答案是,第一轮计算后,a 为:"+ a +";b为:"+b +";第一次计算sum为:"+ sum +"<br/>");
sum = ( (++a) + 3 ) / (2 - (--b) ) * 3;
document.write( "再一次计算后,我认为 a 的值是:" + 6 + " b的值是:" 1 ? + "sum 的值是:" + 27 +"<br/>");
document.write( "答案是,第二轮计算后,a 为:" + a + ";b为:" + b +";第二次计算sum为:"+ sum +",sum的类型也发生变化了。");
</script>
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