字符串操作c++

#include <iostream>
#include <string>
#include <algorithm>

using namespace std;

int main() {
	int n;
	string s;
	cin >> n >> s;
	bool reversed = false;
	
	for (int i = 0; i < n; ++i) {
		string op;
		cin >> op;
		if (op == "F" || op == "B") {
			string str;
			cin >> str;
			if (op == "F") {
				if (!reversed) {
					s = str + s;
				} else {
					reverse(str.begin(), str.end());
					s += str;
				}
			} else { // B 操作
				if (!reversed) {
					s += str;
				} else {
					reverse(str.begin(), str.end());
					s = str + s;
				}
			}
		} else { // R 操作
			reversed = !reversed;
		}
	}
	
	if (reversed) {
		reverse(s.begin(), s.end());
	}
	cout << s << endl;
	return 0;
}