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@@ -0,0 +1,53 @@
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+<!DOCTYPE html>
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+<html lang="en">
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+<head>
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+ <meta charset="UTF-8">
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+ <meta http-equiv="X-UA-Compatible" content="IE=edge">
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+ <meta name="viewport" content="width=device-width, initial-scale=1.0">
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+ <title>Document</title>
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+</head>
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+<body>
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+ <script>
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+ let s = new Set()
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+ let s2 = new Set([1,2,3,4])
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+ console.log(s2) //{1,2,3,4}
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+
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+ //元素个数
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+ console.log(s2.size)
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+ //添加
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+ s2.add(5)
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+ console.log(s2)
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+ //删除
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+ s2.delete(1)
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+ //检测
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+ console.log(s2.has(5))
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+ //清空
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+ //s2.clear();
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+ //可以使用for of
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+ for(let v of s2){
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+ console.log(v)
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+ }
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+
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+ //集合实践
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+ //数组去重
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+ let arr = [1,2,4,3,2,4,5,3]
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+ // let result = [...new Set(arr)]
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+ // console.log(result)
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+
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+ //交集
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+ let arr2 = [4,3,5,7,8]
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+ let result = [...new Set(arr)].filter(item=>{
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+ return arr2.includes(item)
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+ })
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+ console.log(result)
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+
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+ //并集
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+ let union = new Set([...arr,...arr2])
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+ console.log(union)
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+
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+ //差集
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+ let diff = [...new Set(arr)].filter(item=>!(new Set(arr2).has(item)))
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+ console.log(diff)
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+ </script>
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+</body>
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+</html>
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