搜索算法

function sequentialSearch(arr,val){
    for(let i = 0;i < arr.length;i++){
        if(val == arr[i]){
            return i
        }
    }
    return -1
}　

function binarySearch(arr,val){
    const sortArr = quickSort(arr)
    let lowIndex = 0
    let highIndex = sortArr.length-1
    while(lowIndex <= highIndex){
        let mid = Math.floor((lowIndex + highIndex) / 2)
        if(val == sortArr[i]){
            return mid
        }else if(val > sortArr[mid]){
            lowIndex = mid + 1
        }else if(val < sortArr[mid]){
            highIndex = mid -1
        }else{
            return -1
        }
    }
}

function shuffle(arr){
    for(let i = arr.length-1;i > 0;i--){
        const randomIndex = Math.floor(Math.random() * (i+1))
        swap(arr,i,randomIndex)
    }
}