#pragma region template #include using namespace std; // clang-format off using ll = long long; using vl = vector; using vvl = vector; using ld = long double; using vld = vector; using vvld = vector; using pll = pair; using vpll = vector; using vvpll = vector; using vb = vector; using vvb = vector>; using vs = vector; using mll = map; template using V = vector; template using VV = V>; template using VVV = V>; template using max_heap = priority_queue; template using min_heap = priority_queue, greater>; constexpr ll inf = 3001001000100100100LL; #define endl '\n' #define _overload(_1, _2, _3, name, ...) name #define rep(...) _overload(__VA_ARGS__, _rep, _rep2,)(__VA_ARGS__) #define repc(...) _overload(__VA_ARGS__, _repc, _repc2,)(__VA_ARGS__) #define repr(...) _overload(__VA_ARGS__, _repr, _repr2,)(__VA_ARGS__) #define reprc(...) _overload(__VA_ARGS__, _reprc, _reprc2,)(__VA_ARGS__) #define _rep(i,k,n) for(ll i=(k) , i##_xxxx=(n); i < i##_xxxx; ++i) #define _repc(i,k,n) for(ll i=(k) , i##_xxxx=(n); i <=i##_xxxx; ++i) #define _repr(i,k,n) for(ll i=(n)-1, i##_xxxx=(k); i >=i##_xxxx; --i) #define _reprc(i,k,n) for(ll i=(n) , i##_xxxx=(k); i >=i##_xxxx; --i) #define _rep2(i,n) _rep(i,0,n) #define _repc2(i,n) _repc(i,1,n) #define _repr2(i,n) _repr(i,0,n) #define _reprc2(i,n) _reprc(i,1,n) #define rall(o) rbegin(o), rend(o) #define all(o) begin(o), end(o) template ll sz(const C& c) { return static_cast(c.size()); } template bool chmax(T& m, const T& v){ if (m < v){ m = v; return true; } return false; } template bool chmin(T& m, const T& v){ if (v < m){ m = v; return true; } return false; } template T cdiv(const T& a, const T& b){ return (a + b - 1) / b; } template T rdiv(const T& a, const T& b){ return (a + b / 2) / b; } template string join(const T& v, const S& sep ){ stringstream ss; bool f = false; for (const auto& e : v){ if (f) ss << sep; f = true; ss << e;} return ss.str(); } template string join(const T& v, const S& sep, const U& ...args){ stringstream ss; bool f = false; for (const auto& c : v){ if (f) ss << sep; f = true; ss << join(c, args...); } return ss.str(); } template ostream& operator<<(ostream& os, const vector& seq){ os << '[' << join(seq, ",") << ']'; return os; } template ostream& operator<<(ostream& os, const vector>& seq){ os << '[' << join(seq, ",\n ") << ']'; return os; } template ostream& operator<<(ostream& os, const deque& seq){ os << '[' << join(seq, ",") << ']'; return os; } template ostream& operator<<(ostream& os, const set& seq){ os << '{' << join(seq, ",") << '}'; return os; } template ostream& operator<<(ostream& os, const unordered_set& seq){ os << '{' << join(seq, ",") << '}'; return os; } template ostream& operator<<(ostream& os, const map& seq){ os << '{'; bool f = false; for (const auto& e : seq){ if (f) os << ','; f = true; os << e.first << ":" << e.second; } os << '}'; return os; } template ostream& operator<<(ostream& os, const pair& pa){ os << '(' << pa.first << ',' << pa.second << ')'; return os; } #if LOCAL #define debug(...) _debug(__VA_ARGS__, __LINE__) #else #define debug(...) #endif void print() { std::cout << '\n'; } template void print(const S& a){ std::cout << a << '\n'; } template void _debug(const S& a){ std::cerr << "(L:" << std::setw(3) << a << ")\n"; } template void print(const S& a, const T&... args){ std::cout << a << ' '; print(args...); } template void _debug(const S& a, const T&... args){ std::cerr << a << ' '; _debug(args...); } struct setup_main { setup_main() { std::cin.tie(nullptr); std::ios::sync_with_stdio(false); std::cout << fixed << setprecision(15); } } setup_main_; // clang-format on #pragma endregion #include #include #ifdef LOCAL const ll M = 10; #else const ll M = 500000; #endif template struct Compress { vector inv; Compress(vector a = {}) : inv(a) {} void push(T val) { inv.push_back(val); } void compress() { sort(all(inv)); inv.erase(unique(all(inv)), inv.end()); } ll zip(T val) { return lower_bound(all(inv), val) - inv.begin(); } T unzip(ll idx) { assert(0 <= idx and idx < sz(inv)); return inv[idx]; } size_t size() { return inv.size(); } }; void solve(ll H, ll W, vector>& A) { vvpll B(M + 1); rep(y, H) rep(x, W) { if (A[y][x] != 0) B[A[y][x]].emplace_back(y, x); } ll ans = 0; for (auto& v : B) { if (sz(v) == 0) continue; if (sz(v) == 1) { ans++; continue; } Compress row, col; for (auto&& [y, x] : v) { row.push(y); col.push(x); } row.compress(), col.compress(); ll h = row.size(), w = col.size(); atcoder::mf_graph G(h + w + 2); ll s = h + w, t = s + 1; rep(y, h) G.add_edge(s, y, 1); rep(x, w) G.add_edge(x, t, 1); for (auto [y, x] : v) { y = row.zip(y); x = col.zip(y); G.add_edge(y, x, 1); } ll f = G.flow(s, t); debug(v, f); ans += f; } print(ans); } int main() { ll H, W; cin >> H >> W; vector> A(H, vector(W)); rep(j, H) { rep(i, W) { cin >> A[j][i]; } } solve(H, W, A); }