[Leetcode] Excel Sheet Column Title

Question:

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

For example:

    1, A    2, B    3, C    ...    AA, Z        

1. Classification of types of questions:

2. Idea: Convert decimal to 26 binary

3. Complexity of Time:

4. Code:

     Public String converttotitle (int  n) {        StringBuilder StringBuilder=new  StringBuilder ();         while (n>0)        {            n-=1;            Stringbuilder.append ((char) (' A ' + ((n)%26));            n/=26;        }         return stringbuilder.reverse (). toString ();    }

5. Optimization:

Since it starts at 1 instead of 0, we subtract 1.

 Public class Solution {    public String converttotitle (int  n) {        StringBuilder StringBuilder =new  StringBuilder ();          while (n>0)        {            stringbuilder.append(char) (' A ' + ((n-1)%26));            n=(n-1)/26;        }         return stringbuilder.reverse (). toString ();    }}

6. Extension:

Decimal and arbitrary binary transfer

[Leetcode] Excel Sheet Column Title