一、去重
1、借助額外變數空間-es5
var arr = [1,3,4,5,6,6,7,3,3,3]
var newarr =
var obj = {}
function removeduplicates(arr)
} return newarr;
}removeduplicates(arr);
//[1,3,4,5,6,7]
var arr = [1,3,4,5,6,6,7,3,3,3]
var removeduplicates = function(nums)
}return nums;
};removeduplicates(arr);
//[1,3,4,5,6,7]
const obj =
const arr = [1,3,4,5,6,6,7,3,3,3,obj,obj]
const os = new set(arr);
const newarr = [...os];//[1, 3, 4, 5, 6, 7,]
const arr1 = [1,3,4,5,3]
const arr2 = [1,2,7,8,3]
const os = new set([...arr1,...arr2])
console.log([...os]);//[1,2,3,4,5,7,8]
const arr1 = [1,3,4,5,3]
const arr2 = [1,2,7,8,3]
const os1 = new set(arr1)
const os2 = new set(arr2)
const newarr = [...os1].filter(ele => os2.has(ele))
console.log(newarr);//[1,3]
const arr1 = [1,3,4,5,3]
const arr2 = [1,2,7,8,3]
const os1 = new set(arr1)
const os2 = new set(arr2)
const newarr1 = [...os1].filter(ele => !os2.has(ele))
const newarr2 = [...os2].filter(ele => !os1.has(ele))
const newarr = [...newarr1,...newarr2];
console.log(newarr);//[2,3,4,5,7,8]
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