171.excel表列序号.py

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# @lc app=leetcode.cn id=171 lang=python3
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# [171] Excel表列序号
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# https://leetcode-cn.com/problems/excel-sheet-column-number/description/
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# algorithms
# Easy (63.24%)
# Total Accepted:    11.3K
# Total Submissions: 17.9K
# Testcase Example:  '"A"'
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# 给定一个Excel表格中的列名称，返回其相应的列序号。
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# 例如，
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# ⁠   A -> 1
# ⁠   B -> 2
# ⁠   C -> 3
# ⁠   ...
# ⁠   Z -> 26
# ⁠   AA -> 27
# ⁠   AB -> 28 
# ⁠   ...
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# 
# 示例 1:
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# 输入: "A"
# 输出: 1
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# 示例 2:
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# 输入: "AB"
# 输出: 28
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# 示例 3:
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# 输入: "ZY"
# 输出: 701
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# 致谢：
# 特别感谢 @ts 添加此问题并创建所有测试用例。
# 
#
class Solution:
    def titleToNumber(self, s: str) -> int:
       result = 0
       for i ,x in enumerate(s):
           result += (ord(x)-64) * (26**(len(s)-i-1))
       return result