后面四个测试样例都WA了，求大佬找找错误

#include <bits/stdc++.h>
#define _for(i, a, b) for (int i = (a); i < (b); ++i)
#define _rep(i, a, b) for (int i = (a); i <= (b); ++i)
using namespace std;
int maxW = 0;
stringstream ss;


void solution(int& cnt, int w, int &L, int &flag, stack<string> &IStack, map<string, int> &IMap, int flag2)
{
    int currentW = w;
    while (true)
    {
        w = currentW;
        if (L == 0){
            //g_cnt = cnt;
            return;
        }
        string C;
        cin >> C;
        L--;
        if (C == "F")
        {
            cnt ++;
            string i, x, y;
            cin >> i >> x >> y;
            if (IMap.count(i) && IMap[i] != 0)
            {
                flag = 1;
                return;
            }
            else
            {
                IStack.push(i);
                IMap[i] = 1;
            }

            //  判断x,y大小关系
            if (!flag2)
            {

                if (x == "n" && y != "n")
                {
                    flag2 = 1;
                }
                else if (y == "n" && x != "n")
                {
                    w ++;
                    maxW = max(maxW,w);
                }
                else if (y == "n" && x == "n")
                {
                }
                else
                {
                    int temp1,temp2;
                    ss << x;
                    ss >> temp1;
                    ss.clear();

                    ss << y;
                    ss >> temp2;
                    ss.clear();
                    if(x <= y){

                    }else
                    {
                        flag2 = 1;
                    }
                    

                }
            }

            solution(cnt, w, L, flag, IStack, IMap, flag2);
        }
        else
        {

            cnt--;
            if (!IStack.empty())
            {
                string i = IStack.top();
                IStack.pop();
                IMap[i] = 0;
                return;
            }
            else
            {
                flag = 1;
                return;
            }

            if (cnt < 0)
            {
                flag = 1;
                return;
            }
            return;
        }
    }




    return;
}
//  https://www.luogu.com.cn/problem/P3952
int main()
{
    ios::sync_with_stdio(0); //解决c++输入输出流被卡问题
    int t;
    cin >> t;
    
    while (t--)
    {
        int flag = 0;
        int L;
        string str;
        cin >> L >> str;
        int cnt = 0;
        int w = 0;
        string res;
        stack<string> IStack;
        map<string, int> IMap;
        solution(cnt, w, L, flag, IStack, IMap, 0);
        if (flag || cnt != 0)
        {
            cout << "ERR" << endl;
        }
        else
        {
            if (maxW == 0)
            {
                res = "O(1)";
            }
            else
            {
                ss << maxW;
                string temp;
                ss >> temp;
                ss.clear();
                res = "O(n^" + temp + ")";
            }
            if (res == str)
            {
                cout << "Yes" << endl;
            }
            else
            {
                cout << "No" << endl;
            }
        }
        maxW = 0;
    }

    system("pause");
    return 0;
}