README.md

171. Excel 表列序号

English Version

题目描述

给定一个Excel表格中的列名称，返回其相应的列序号。

例如，

    A -> 1
    B -> 2
    C -> 3
    ...
    Z -> 26
    AA -> 27
    AB -> 28 
    ...

示例 1:

输入: "A"
输出: 1

示例 2:

输入: "AB"
输出: 28

示例 3:

输入: "ZY"
输出: 701

致谢：
特别感谢 @ts 添加此问题并创建所有测试用例。

解法

Python3

class Solution:
    def titleToNumber(self, columnTitle: str) -> int:
        res = 0
        for c in columnTitle:
            res = res * 26 + (ord(c) - ord('A') + 1)
        return res

Java

class Solution {
    public int titleToNumber(String columnTitle) {
        int res = 0;
        for (char c : columnTitle.toCharArray()) {
            res = res * 26 + (c - 'A' + 1);
        }
        return res;
    }
}

TypeScript

function titleToNumber(columnTitle: string): number {
  let res: number = 0;
  for (let char of columnTitle) {
    res = res * 26 + char.charCodeAt(0) - 64;
  }
  return res;
}

C++

class Solution {
public:
    int titleToNumber(string columnTitle) {
        int res = 0;
        for (char c : columnTitle) {
            res = res * 26 + (c - 'A' + 1);
        }
        return res;
    }
};

Go

func titleToNumber(columnTitle string) int {
	res := 0
	for _, c := range columnTitle {
		res = res*26 + int(c-'A'+1)
	}
	return res
}

...