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js数字溢出问题
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<h2 id="JavaScript数字超过边界值-无法保证低位数字的精度"><a href="#JavaScript数字超过边界值-无法保证低位数字的精度" class="headerlink" title="JavaScript数字超过边界值,无法保证低位数字的精度"></a>JavaScript数字超过边界值,无法保证<code>低位数字</code>的精度</h2><p> 今天在群上讨论说数字精度溢出问题<br> 然后有人举出了,下图的情况:<br> <img src="/images/2016-06-01.jpg"></p>
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<p>由图片看出觉得对哇,好想不会溢出,会被自动处理为科学计算法<br>但是看下图,你会知道其实还是溢出的<br> <img src="/images/2016-06-01-1.jpg"><br>超过边界的时候会影响<code>低位数字</code>的精度,所以图1看不出什么影响<br>图2的<code>parseInt("1".repeat(53),2)+1</code>;输出<code>9 007 199 254 740 992</code>,<br><code>parseInt("1".repeat(53),2)+2</code>;也输出<code>9 007 199 254 740 992</code> </p>
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