Sort Letters by case

Given a string which contains only letters. Sort it by lower case first and upper case second.

Example

"abAcD" for, a reasonable "acbAD" answer is

With the negative numbers in front, the positive numbers are placed in the following topic.

Time Complexity of O (n)

Find the first capital letter, record its subscript as I, then the lowercase letter must appear after I, after I find the first occurrence of the lowercase letter J. Exchange I, J. Note: The letters between I and J must be uppercase. Proceed in turn.

1  Public classSolution {2     /** 3      *@paramchars:the Letter Array-should sort by case4      *@return: void5      */6      Public voidSortletters (Char[] chars) {7         if(Chars = =NULL|| Chars.length = = 0) {8             return;9         }Ten         inti = 0; One          for(i = 0; i < chars.length; i++) { A             if(Chars[i] >= ' A ' && chars[i] <= ' Z ') { -                  Break; -             } the         } -          for(intj = i + 1; J < Chars.length; J + +) { -             if(Chars[j] >= ' A ' && chars[j] <= ' z ') { -                 Chartemp =Chars[i]; +Chars[i] =Chars[j]; -CHARS[J] =temp; +i++; A             } at         } -         return; -     } -}

Sort Letters by case