PAT1089

好坑啊，考试的时候因为一个1分的点卡了很长时间，D题都没有看。

坑点在于，直到变化为止，再把这个数组打出来。另外还考察了基本排序算法，merge sort这大概是我第一次写iteration版本，越写越顺，也算是一件好事，insert sort真的是卡了很久，基本功不行，寒假回去看算法书的时候这些算法都用JAVA写一遍吧

#include <fstream>
#include <iostream>
#include <vector>
#include <algorithm>

using namespace std;

//#define OJ

#ifdef OJ
#define fin cin
#else
ifstream fin("in.txt");
#endif

vector<int> merge_vec;
vector<int> insert_vec;
vector<int> target;
vector<int> input;
int n;

#define MAX 0x70000000

int merge_sublist;
int merge_num;
int insert_i;

bool merge_sort(){
    int sublist = n;
    int num = 1;
    bool found = false;

    while (sublist != 1){
        int list_cnt = 0;
        for (int i = 0; i < sublist; i += 2){
            list_cnt++;
            vector<int> s1, s2;
            int s1_start = i * num;
            int s1_end = s1_start + num > n ? n : s1_start + num;
            int s2_start = s1_end;
            int s2_end = s2_start + num > n ? n : s2_start + num;
            int idx = i * num;

            int cnt = 0;
            while (idx < n && cnt++ < num){
                s1.push_back(merge_vec[idx]);
                idx++;
            }
            cnt = 0;
            while (idx < n && cnt++ < num){
                s2.push_back(merge_vec[idx]);
                idx++;
            }

            vector<int> tmp;
            int p1 = s1_start, p2 = s2_start;
            while (p1 != s1_end || p2 != s2_end){
                int v1 = p1 == s1_end ? 0x70000000 : merge_vec[p1];
                int v2 = p2 == s2_end ? 0x70000000 : merge_vec[p2];

                if (v1 < v2){
                    tmp.push_back(v1);
                    p1++;
                }
                else {
                    tmp.push_back(v2);
                    p2++;
                }
            }

            for (int i = s1_start; i < s2_end; i++)
                merge_vec[i] = tmp[i - s1_start];
        }
        sublist = list_cnt;
        num *= 2;
        bool flag = true;
        for (int i = 0; i < n; i++){
            if (target[i] != merge_vec[i]){
                flag = false;
                break;
            }
        }
        if (flag){
            found = true;
            merge_sublist = sublist;
            merge_num = num;
        }
        if (found && !flag){
            return true;
        }
    }
    return false;
}

bool insert_sort(){
    bool found = false;
    for (int i = 0; i < n; i++){
        int j = 0;
        for (; j < i; j++){
            if (insert_vec[j] > insert_vec[i])
                break;
        }
        int swap_num = insert_vec[i];
        for (int k = i; k > j; k--){
            insert_vec[k] = insert_vec[k - 1];
        }
        insert_vec[j] = swap_num;

        bool flag = true;
        for (int i = 0; i < n; i++){
            if (insert_vec[i] != target[i]){
                flag = false;
                break;
            }
        }
        if (flag){
            insert_i = i + 1;
            found = true;
        }
        if (found && !flag){
            return true;
        }
    }

    return false;
}

int main(){
    fin >> n;

    target.resize(n);
    input.resize(n);

    for (int i = 0; i < n; i++){
        fin >> input[i];
    }
    for (int i = 0; i < n; i++){
        fin >> target[i];
    }

    merge_vec = input;
    bool res = merge_sort();

    if (res){
        cout << "Merge Sort" << endl;
        cout << merge_vec[0];
        for (int i = 1; i < n; i++){
            cout << " " << merge_vec[i];
        }
        cout << endl;
        return 0;
    }

    insert_vec = input;
    res = insert_sort();

    if (res){
        cout << "Insertion Sort" << endl;
        cout << insert_vec[0];
        for (int i = 1; i < n; i++){
            cout << " " << insert_vec[i];
        }
        cout << endl;
        return 0;
    }


    return 0;
}