@[TOC](969. 煎饼排序)

读题

解题

class Solution {
public:
    vector<int> revet(vector<int> &arr,int index,vector<int> &ind ){
        int v;
        for(int i =0,j =index ;i<j ;i++,j--){
            swap(arr[i],arr[j]);
            ind[arr[i]] = i;
            ind[arr[j]] = j;
        }
        return arr;
    }
    vector<int> pancakeSort(vector<int>& arr) {
        vector<int> ind(arr.size()+1);
        vector<int> ret;
        for(int i = 0;i<arr.size();i++) ind[arr[i]] = i;
        for(int i = arr.size();i>=1;i--){
            if(ind[i] != 0)ret.push_back(ind[i]+1);
            revet(arr,ind[i],ind);
            if(i != 1)ret.push_back(i);
            revet(arr,i - 1, ind);
        }
        return ret;
    }
};