直接法

#include <vector>
class Solution {
  public:
    vector<int> solve(int n, int m, vector<int>& a) {
        m = m % n;
        vector<int> res;
        for (int i = n - m; i < n; i++) {
            res.push_back(a[i]);
        }
        for (int i = 0; i < n - m; i++) {
            res.push_back(a[i]);
        }
        return res;
    }
};

三次翻转

class Solution {
  public:
    vector<int> solve(int n, int m, vector<int>& a) {
        m = m % n;
        reverse(a.begin(), a.end());
        reverse(a.begin(), a.begin()+m);
        reverse(a.begin()+m, a.end());
        return a;
    }
};