SOURCE

/**
 * 获取几个字之后换行的数据
 */
function test(str, num) {
    let value = ''
    let strNum = 0
    let substrCount = Math.ceil(str.length / num)
    while (strNum < substrCount) {
        let strSubstr = str.substr(strNum * num, num)
        console.log(strNum, strSubstr)
        strNum += 1
    }
    return substrCount
}
// console.log(test('北京市第一人民医院', 4))

/**
 * 获取excle表格列号 length数据的长度
 */
function getSheetColumn(length) {
    let arr = ['A','B','C','D','E','F','G',
        'H','I','J','K','L','M','N','O','P','Q',
        'R','S','T','U','V','W','.X','Y','Z']
    let bei = Math.ceil(length/arr.length)
    let returnArr = []
     for(let n = 1;n<=length;n++){
         let secendNum = n%arr.length==0?26: n%arr.length
         let i = Math.ceil( n/arr.length)
            if(i==1){
                returnArr.push(arr[secendNum-1])
            }else{
                let secendNum = n%arr.length==0?26: n%arr.length
                returnArr.push(arr[i-2]+arr[secendNum-1])
            }
        }
    return returnArr
}
console.log(getSheetColumn(19))