LintCode 8---旋转字符串

Posted 2021-11-27 cnmoti

/*
给定一个字符串（以字符数组的形式给出）和一个偏移量，根据偏移量原地旋转字符串(从左向右旋转)
 */
public class Lint8 {
    public static void main(String[] args) {
        
    }
    public void rotateString(char[] str, int offset) {
        // write your code here
        if (str == null || str.length == 0)return;
        offset = offset % str.length;
        reverse(str, 0, str.length - offset - 1);
        reverse(str, str.length - offset, str.length - 1);
        reverse(str, 0, str.length - 1);
    }
    private void reverse(char[] str, int start, int end) {
        for (int i = start, j = end; i < j; i++, j--) {
            char temp = str[i];
            str[i] = str[j];
            str[j] = temp;
        }
    }
}