三次翻转(分治)
#include <iostream>
using namespace std;
void reverse(char c[], int begin, int end){
for (int i = 0; i < (end - begin + 1) / 2; ++i) {
char temp;
temp = c[begin + i];
c[begin + i] = c[end - i];
c[end - i] = temp;
}
}
void leftMove(char c[], int n, int k){
int m = k % n;
reverse(c, 0