171. [LeetCode]Excel Sheet Column Number [easy] (java)

2018-06-16 234 words One minute views

### 题目描述：

Related to question Excel Sheet Column Title

Given a column title as appear in an Excel sheet, return its corresponding column number.

For example:

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

题目大意：

解题思路：

26进制转化为10进制

Python代码：

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class Solution:
# @param s, a string
# @return an integer
def titleToNumber(self, s):
  ans = 0
  for e in s:
      ans = ans * 26 + ord(e) - ord('A') + 1
  return ans

Java代码：

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class Solution {
	public int titleToNumber(String s) {
		int result = 0;
		for (int i = 0; i < s.toCharArray().length; i++) {
			result = result * 26 + s.toCharArray()[i] - 'A' + 1;
		}
		return result;
	}
}	  