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// clang-format off
#include<bits/stdc++.h>
using namespace std;
using LL=long long;
#define FOR(i,l,r) for(auto i=(l);i<=(r);++i)
#define REP(i,n) FOR(i,0,(n)-1)
#define ssize(x) int(x.size())
auto operator<<(ostream&o,auto p)->decltype(p.first,o){return o<<"("<<p.first<<", "<<p.second<<")";}
auto operator<<(ostream&o,auto x)->decltype(x.end(),o){o<<"{";int i=0;for(auto e:x)o<<(", ")+2*!i++<<e;return o<<"}";}
#ifdef DEBUG
#define debug(x...) cerr<<"["#x"]: ",[](auto...$){((cerr<<$<<"; "),...);}(x),cerr<<'\n'
#else
#define debug(...) {}
#endif
// clang-format on

struct Tree
{
    int level;
    int nleafes;
};

struct Node
{
    int tree_id;
    bool isleaf;
};

int nlevels;
vector<Tree> trees;
vector<int> needed;

Node
makeRoot(int level)
{
    trees.push_back({.level = level, .nleafes = 1});
    needed[level + 1] -= 1;
    return {.tree_id = ssize(trees) - 1, .isleaf = true};
}

Node
makeChild(int level, Node &parent)
{
    auto &tree = trees[parent.tree_id];

    // Parent is no longer a leaf
    if (parent.isleaf) {
        parent.isleaf = false;
        tree.nleafes -= 1;
        needed[level] += 1;
    }

    // Create a leaf
    needed[level + 1] -= 1;
    tree.nleafes += 1;
    return {.tree_id = parent.tree_id, .isleaf = true};
}

int
main()
{
    cin.tie(0)->sync_with_stdio(0);
    cin >> nlevels;
    needed.resize(nlevels + 1, 0);

    // Create the first level
    int n;
    vector<Node> curr_level, prev_level;
    cin >> n;
    REP (i, n) curr_level.emplace_back(makeRoot(0));

    // Create remaining levels
    FOR (level, 1, nlevels - 1) {
        swap(curr_level, prev_level);
        curr_level.clear();
        cin >> n;
        REP (i, n) {
            int j;
            cin >> j;
            if (j == 0) curr_level.emplace_back(makeRoot(level));
            else curr_level.emplace_back(makeChild(level, prev_level[j - 1]));
        }
    }

    // Add needed agents for trees
    debug(needed);
    for (const auto &tree : trees) {
        needed[tree.level] += tree.nleafes;
        debug(tree.level, tree.nleafes);
    }
    debug(needed);

    // Calculate score
    int max_needed = needed[0];
    FOR (level, 1, nlevels) {
        needed[level] += needed[level - 1];
        max_needed = max(max_needed, needed[level]);
    }
    debug(needed);
    cout << max_needed << "\n";
    return 0;
}