func_code_string: #include <bits/stdc++.h>   const int maxN = 2000;   const unsigned int mod = 998244353;   constexpr int inf = INT_MAX;   class Array {    public:     inline const int *begin() const { return data; }     inline const int *end() const { return endPtr; }     inline void push_back(const int x) { *(endPtr++) = x; }     inline size_t size() const { return endPtr - data; }     template <class T>     inline void foreach (T fun) const {       std::for_each<const int *>(data, endPtr, fun);     }       private:     int data[maxN + 10], *endPtr = data;   };   Array edgeIn[maxN + 10], edgeOut[maxN + 10];   int originDegree[maxN + 10], degree[maxN + 10];   inline void reset(const int n) {     std::memcpy(degree, originDegree, sizeof(degree[0]) * n);   }   void readGraph(const int n) {     for (int i = 0; i < n; ++i) {       static char str[maxN + 10];       std::cin >> str;       for (int j = 0; j < n; ++j)         if (str[j] ==  1 ) {           edgeIn[j].push_back(i);           edgeOut[i].push_back(j);           ++originDegree[i];         }     }   }   bool isStrongConnect(const int n) {     std::sort(degree, degree + n);     int sum = 0;     for (int i = 0; i + 1 < n; ++i) {       sum += degree[i];       if (i * (i + 1) / 2 == sum) return false;     }     return true;   }   void reverseSet(const int n, const unsigned int set) {     for (int i = 0; i < n; ++i)       for (auto to : edgeOut[i])         if ((((set) >> (i)) & 0x01u) ^ (((set) >> (to)) & 0x01u)) {           --degree[i];           ++degree[to];         }   }   inline bool checkSet(const int n, const unsigned int set) {     reset(n);     reverseSet(n, set);     return isStrongConnect(n);   }   void reverseSingle(const int vertex) {     edgeOut[vertex].foreach ([](int p) { ++degree[p]; });     edgeIn[vertex].foreach ([](int p) { --degree[p]; });     degree[vertex] = edgeIn[vertex].size();   }   inline bool checkSingle(const int n, const int vertex) {     reset(n);     reverseSingle(vertex);     return isStrongConnect(n);   }   unsigned int factor(const unsigned int n) {     unsigned int ret = 1;     for (unsigned int i = 2; i <= n; ++i) ret = (ret * i) % mod;     return ret;   }   std::pair<int, int> enumSet(const int n) {     int count = inf, solution = 0;     const unsigned int msk = 1u << n;     for (unsigned int i = 1; i < msk; ++i) {       const int cnt = __builtin_popcount(i);       if (cnt <= count && checkSet(n, i)) {         if (cnt == count)           ++solution;         else {           solution = 1;           count = cnt;         }       }     }     return std::make_pair(count,                           count != inf ? (solution * factor(count)) % mod : 0);   }   std::pair<int, int> enumVertex(const int n) {     int solution = 0;     for (int i = 0; i < n; ++i) solution += checkSingle(n, i);     return std::make_pair(1, solution);   }   int main() {     std::ios::sync_with_stdio(false);     int n;     std::cin >> n;     readGraph(n);     reset(n);     if (isStrongConnect(n)) {       std::cout <<  0 1 n ;       return 0;     }     const auto [count, solution] = n <= 6 ? enumSet(n) : enumVertex(n);     if (count == inf)       std::cout <<  -1 n ;     else       std::cout << count <<     << solution <<   n ;     return 0;   }   