SOURCE

            const _getUniqueNums = (start,end,n) => {
                // 补全代码
    let resArr=[]
    if(n>(end-start)||n<=0) return false
    for(let i=0;i<n;i++){
        pushRdMumToArr(start,end,resArr)
        
    }
    return resArr
 
}
function pushRdMumToArr(start,end,arr){
    let randomNum=getRandom(start,end)
    if(!arr.includes(randomNum)){
        arr.push(randomNum)
        return
    }else{
        pushRdMumToArr(start,end,arr)
    }
    
}
function getRandom(min,max){
    
    return Math.floor(Math.random()*(max-min)+min)
}
console.log(_getUniqueNums(2,8,4))

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