Leetcode:excel Sheet Column Title

return Its corresponding column title as appear in an Excel sheet. For example:    1, A    2, B    3, C    ...     AA     , Z    

This problem is my Microsoft onsite encountered a problem, did not encounter this problem is really a bit difficult to understand suddenly (I was the problem should do bad, from most significant digit do, and forget N to-1). This question is actually the decimal conversion 26 binary, and is starting from 1 10 binary conversion

The essence is a binary conversion, converting N to 26, and the conversion process is as follows (26 decimal numbers in parentheses):

1-> (1)->a2-> (2)->b ... 26-> (Ten)->z27-> (one)->aa28-> (a)->ab ..... 52-> (->az53->)->ba

Starting from least significant digit, divide by 26 to take the remainder continuously.

This is my method:

1  Public classSolution {2      PublicString Converttotitle (intN) {3         if(n <= 0)return"";4StringBuffer res =NewStringBuffer ();5          while((n-1)/26 > 0) {6Res.insert (0, (Char) (' A ' + (n-1)%26));7n = (n-1)/26;8         }9Res.insert (0, (Char) (' A ' + (n-1)%26));Ten         returnres.tostring (); One     } A}

The way people are inspired by others online:

1  Public classSolution {2String Converttotitle (intN) {3StringBuffer str =NewStringBuffer ();4          while(n! = 0){5             intr = N 26;6n= N/26;7             if(r = = 0) {//as an integer multiple of 26, this bit is set to Z,n minus 18Str.insert (0, ' Z ');9n--;Ten             } One             Else{ AStr.insert (0, (Char) (' A ' +r-1)); -             } -         } the         returnstr.tostring (); -     } -}

Leetcode:excel Sheet Column Title