暴力循环
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<head><meta charset="UTF-8"><meta name="viewport" content="width=device-width, initial-scale=1.0"><title>质数练习</title>
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<body><script>function isPrime(num){if(num === 0 || num === 1){return false}if(num === 2){return true}for(let i = num - 1;i > 1;i--){if(num % i === 0){return false}}return true}let num = +prompt('请输入您想判断的数字')let ans = isPrime(num)if(ans){document.write(`${num}是质数`)}else{document.write(`${num}不是质数`)}</script>
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