#include <iostream> #include <string> #include <vector> #include <algorithm> #include <utility> #include <atcoder/modint> using namespace std; using i32 = int32_t; using u32 = uint32_t; using i64 = int64_t; using u64 = uint64_t; #define rep(i,n) for(int i=0; i<(int)(n); i++) const i64 INF = 1001001001001001001; using Modint = atcoder::static_modint<998244353>; int main(){ int N, K; cin >> N >> K; vector<int> A(N); rep(i,N){ string S; cin >> S; int id = 0; for(char c : S) id = id * 5 + '4' - c; A[i] = id; } int K5 = 1; rep(i,K) K5 *= 5; vector<int> C(K5); rep(i,N) C[A[i]]++; for(int k5=1; k5<K5; k5*=5) for(int i=0; i<K5; i+=k5*5) for(int q=i; q<i+k5*4; q+=k5) for(int r=q; r<q+k5; r++) C[r+k5] += C[r]; int ans = 0; rep(i,N) if(C[A[i]] > 1) ans++; cout << ans << endl; return 0; } struct ios_do_not_sync{ ios_do_not_sync(){ ios::sync_with_stdio(false); cin.tie(nullptr); } } ios_do_not_sync_instance;