func_code_string: #include <bits/stdc++.h>   using namespace std;   using ll = long long;   using ld = long double;   using pii = pair<int, int>;   using pll = pair<ll, ll>;   using vi = vector<int>;   using vll = vector<ll>;   constexpr int MOD = 1e9 + 7;   constexpr int INF = INT_MAX;   constexpr ll LLINF = LLONG_MAX;   template <class T>   inline bool setmin(T &a, T b) {     if (a > b) return a = b, 1;     return 0;   }   template <class T>   inline bool setmax(T &a, T b) {     if (a < b) return a = b, 1;     return 0;   }   namespace fastio {   template <class T>   istream &operator>>(istream &os, vector<T> &container) {     for (auto &u : container) os >> u;     return os;   }   template <class T>   ostream &operator<<(ostream &os, const vector<T> &container) {     for (auto &u : container) os << u <<    ;     return os;   }   template <class T1, class T2>   inline istream &operator>>(istream &os, pair<T1, T2> &p) {     return os >> p.first >> p.second;   }   template <class T1, class T2>   ostream &operator<<(ostream &os, const pair<T1, T2> &p) {     return os << p.first <<     << p.second;   }   template <typename... args>   void re(args &...tail) {     ((cin >> tail), ...);   }   template <typename... args>   void pr(args... tail) {     ((cout << tail <<    ), ...);   }   template <typename... args>   void prln(args... tail) {     ((cout << tail <<    ), ...);     cout <<   n ;   }   }  // namespace fastio   using namespace fastio;   namespace debug {   template <typename _T>   inline void _debug(const char *s, _T x) {     cerr << s <<   =   << x <<   n ;   }   template <typename _T, typename... args>   void _debug(const char *s, _T x, args... a) {     while (*s !=  , ) cerr << *s++;     cerr <<   =   << x <<  , ;     _debug(s + 1, a...);   }   }  // namespace debug   using namespace debug;   const int N = 1e5 + 7;   string s;   int n, q;   int nxt[N][26];   int dp[257][257][257];   string rel[3];   int main() {     ios_base::sync_with_stdio(0);     cin.tie(0);     cout.tie(0);     ;     re(n, q, s);     for (int i = (0); i <= (25); i++) nxt[n][i] = nxt[n + 1][i] = n;     for (int i = (n - 1); i >= (0); i--) {       for (int j = (0); j <= (25); j++) {         nxt[i][j] = (s[i] ==  a  + j ? i : nxt[i + 1][j]);       }     }     dp[0][0][0] = -1;     for (int _ = (1); _ <= (q); _++) {       char t;       int x;       re(t, x);       x--;       if (t ==  + ) {         char l;         re(l);         rel[x] += l;         int e0 = (int)(rel[0]).size(), e1 = (int)(rel[1]).size(),             e2 = (int)(rel[2]).size();         int b0 = (x == 0 ? e0 : 0);         int b1 = (x == 1 ? e1 : 0);         int b2 = (x == 2 ? e2 : 0);         for (int a = (b0); a <= (e0); a++) {           for (int b = (b1); b <= (e1); b++) {             for (int c = (b2); c <= (e2); c++) {               auto &v = dp[a][b][c];               v = n;               if (a) setmin(v, nxt[dp[a - 1][b][c] + 1][rel[0][a - 1] -  a ]);               if (b) setmin(v, nxt[dp[a][b - 1][c] + 1][rel[1][b - 1] -  a ]);               if (c) setmin(v, nxt[dp[a][b][c - 1] + 1][rel[2][c - 1] -  a ]);             }           }         }       } else {         rel[x].pop_back();       }       prln(dp[(int)(rel[0]).size()][(int)(rel[1]).size()][(int)(rel[2]).size()] <                    n                ?  YES                 :  NO );     }     exit(0);   }   