8 - 旋转字符

4.18

public class Solution {
    /**
     * @param str: an array of char
     * @param offset: an integer
     * @return: nothing
     */
    public void rotateString(char[] str, int offset) {
        int count = str.length;
        if(count == 0){
            return;
        }
        if(offset == 0){
            return;
        }
        while(offset >= count){
            offset = offset % count;
        }
        
        char[] tmp = new char[count];
        int flag = 0;
        for(int i = count - offset;i < count;i++){
            tmp[flag ++] = str[i];
        }
        int k = 0;
        while(flag < count){
            tmp[flag++] = str[k++];
        }
        for(int h =0;h<count;h++){
            str[h] = tmp[h]; 
        }
        
        
        // write your code here
    }
}