？前为真就执行？号后面的，为假就执行：号后边的
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<body><script>30>20?console.log(11111):console.log(22222)10>20?console.log(11111):console.log(22222)// ？前为真就执行？号后面的，为假就执行：号后边的var sum = 210var youhuisum = sum>200? sum-10 : sumconsole.log(sum,youhuisum)</script>
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