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<title>数组去重排序</title>
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<script>
// 数组去重
// 方法一（原理性）：
var arr = [2, 5, 12, 21, 54, 22, 61, 6, 1, 72, 4, 1, 3, 5, 3, 51, 4, 2, 22]
var result = []
for (var i = 0; i < arr.length; i++) {
var flag = true
for (var j = 0; j < result.length; j++) {
if (arr[i] === result[j]) {
flag = false
break
}
}
if (flag === true) {
result[result.length] = arr[i]
}
}
// 方法二:
// var result = new Set(arr)
// 数组排序
var res = result.sort(function(a, b) {
// return a - b
return b - a
})
// 倒叙 reverse() 相当于return b-a
// console.log(result.reverse())
console.log(result)
</script>
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