SOURCE

// 找出两个有序数组的中位数
// [1, 3] [2] => 2
// [1, 4] [2, 3] => 2+3/2

const fn = (arr1, arr2) => {
    let len = arr1.length + arr2.length
    let cursor = len/2;
    let i = 0, j = 0
    let res, pre
    while((i + j) <= cursor){
        if(arr1[i] === undefined){
            pre = res
            res = arr2[j]
            j++
            continue
        }
        if(arr2[j] === undefined){
            pre = res
            res = arr1[i]
            i++
            continue
        }
        if(arr1[i] < arr2[j]){
            pre = res
            res = arr1[i]
            i++
        } else {
            pre = res
            res = arr2[j]
            j++
        }
    }
    if(len % 2 === 0){
        return (res + pre)/2
    }
    return res
}

console.log(fn([1, 3, 6, 8], [2, 4, 5, 7]))