【topcoder】LR

#include <iostream>
#include <vector>
#include <numeric>
#include <deque>

using namespace std;

class MyList {
private:
    deque<long long> a;
public:

    MyList(const vector<long long> &b) {
        a = deque<long long>();
        for (auto x : b)
            a.push_back(x);
    }

    void execute_L() {
        auto tmp = a;
        for (int i = 1;i<a.size();i++) {
            tmp[i] = tmp[i] + a[i-1];
        }
        tmp[0] += a[a.size() - 1];
        a = tmp;
    }

    void execute_R() {
        execute_L();
        rotate_L();
    }

    long long getSum() {
        return accumulate(a.begin(),a.end(),0LL);
    }

    void rotate_L() {
        auto tmp = a[0];
        a.pop_front();
        a.push_back(tmp);
    }

    bool equal(const MyList &b) {
        return a == b.a;
    }

//    void print() {
//        for (auto x : a) {
//            cout << x << " ";
//        }
//        cout << endl;
//    }
};

class LR {

public:

    LR() {
    }

    string construct(vector<long long> s, vector<long long> t) {
        MyList list1 = MyList(s);
        MyList list2 = MyList(t);
//        list1.print();
//        cout << list1.getSum() << endl;
//        list2.print();
//        cout << list2.getSum() << endl;
        int stepCnt = 0;
        if (list1.getSum())
        while (list1.getSum() < list2.getSum()) {
            list1.execute_L();
            //list1.print();
            stepCnt++;
        }
        if (list1.getSum() != list2.getSum()) return "No solution";

        int rotateCnt = 0;
        while (!list1.equal(list2)) {
            list1.rotate_L();
            rotateCnt++;
            if (rotateCnt > stepCnt) return "No solution";
        }

        string ret = "";
        for (int i = 0;i<rotateCnt;i++) ret+="R";
        while (ret.size() < stepCnt) ret+="L";
        return ret;

    }

private:

};

int main() {

    LR inst = LR();
    cout << inst.construct(vector<long long>{0,0,0,0,0},vector<long long>{0,0,0,1,0}) << endl;

    return 0;
}

思路还是想很快的，就是写个程序老纠结了。完全忍不了以前那种只为了正确的程序，这样就浪费了好多宝贵的比赛时间。而且C++也是忘得差不多了。权当娱乐了，250还是稳切的哈哈。