题解 | #MP3光标位置#

#include <iostream>
using namespace std;
int main() {
    int n;
    string str;
    while (cin >> n >> str) {
        int index = 1;
        int start = 1, end = min(4, n);

        for (int i = 0; i < str.size(); i++) {
            switch (str[i]) {
                case 'U':
                    index = (index -1-1 + n)%n+1;
                    break;
                case 'D':
                    index = index % n +1;
                    break;
            }
            if(index < start)
            {
                start = index;
                end= start +3;
            }
            else if(index > end)
            {
                end=index;
                start =end-3;
            }

        }
        for(int i=start;i<=end;i++)
        {
            cout<<i<<" ";
        }
        cout<<endl;
        cout << index << endl;
    }

    return 0;
}