#include #include #include #include #include #include #include #include #include using namespace std; typedef long long ll; typedef vector vi; typedef vector vvi; #define rep(i,n) for(ll i=0;i<(n);i++) #define pii pair #define piii pair #define mp make_pair #define pb push_back #define ALL(a) (a).begin(),(a).end() #define FST first #define SEC second const int INF = (INT_MAX/2); const ll LLINF = (LLONG_MAX/2); const double eps = 1e-5; const double PI = M_PI; #define DEB cerr<<"!"< mii; int main(){ int n; cin >> n; rep(i,n){ rep(j,3){int a; cin >> a; mii[a]++;} } int ans = 0; int el = 0; rep(i,11){ if(mii[i] >= 2){mii[i]-=2; ans++; i--; continue;} else el += mii[i]; } cout << ans + el/4 << endl; }