Leetcode Excel Sheet Column Title

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

For example:

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

Problem Solving Ideas:

The boundary condition of z= 26 needs to be considered. My code is discussed in detail, the reference code is very clever, with n--

The key is n-- . The minimum in 26-bit number are mapped to 1, not 0.

Java Code:

1.

  PublicString Converttotitle (intN) {if(N < 1) {            return""; } StringBuilder S=NewStringBuilder (); CharA = ' a ';  while(N >= 1) {            intx = n%26; if(x = = 0) {a= ' Z '; N= N/26-1; }Else{a= (Char) (' A ' + x-1); N= N/26;        } s.append (a); }        returns.reverse (). toString (); }

2. Reference code, better.

 PublicString Converttotitle (intN) {if(n <= 0){            Throw NewIllegalArgumentException ("Input is not valid!"); } StringBuilder SB=NewStringBuilder ();  while(N > 0) {n--; CharCH = (Char) (n% + ' A '); N/= 26;        Sb.append (CH); }        returnsb.reverse (). toString (); }

Reference:

1. http://www.programcreek.com/2014/03/leetcode-excel-sheet-column-title-java/

Leetcode Excel Sheet Column Title