1
 2
 3
 4
 5
 6
 7
 8
 9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
#include <bits/stdc++.h>
using namespace std;
#define PII pair<int, int>
#define VI vector<int>
#define VPII vector<PII>
#define LL long long
#define LD long double
#define f first
#define s second
#define MP make_pair
#define PB push_back
#define endl '\n'
#define ALL(c) (c).begin(), (c).end()
#define SIZ(c) (int)(c).size()
#define REP(i, n) for(int i = 0; i < (int)(n); ++i)
#define FOR(i, b, e) for(int i = (b); i <= (int)(e); ++i)
#define FORD(i, b, e) for(int i = (b); i >= (int)(e); --i)
#define ll LL
#define st f
#define nd s
#define pb PB
#define mp MP
#define eb emplace_back
#define siz(c) SIZ(c)
const int inf = 1e9+7;
const ll INF = 1e18L+7;

#define sim template<class n
sim, class s> ostream & operator << (ostream &p, pair<n, s> x)
{return p << "<" << x.f << ", " << x.s << ">";}
sim> auto operator << (ostream &p, n y) ->
typename enable_if<!is_same<n, string>::value, decltype(y.begin(), p)>::type 
{int o = 0; p << "{"; for(auto c: y) {if(o++) p << ", "; p << c;} return p << "}";}
void dor() {cerr << endl;}
sim, class...s> void dor(n p, s...y) {cerr << p << " "; dor(y...);}
sim, class s> void mini(n &p, s y) {if(p>y) p = y;}
sim, class s> void maxi(n &p, s y) {if(p<y) p = y;}
#ifdef DEB
#define debug(...) dor(__FUNCTION__, ":", __LINE__, ": ", __VA_ARGS__)
#else
#define debug(...)
#endif 

#define I(x) #x " =", (x), " "
#define A(a, i) #a "[" #i " =", i, "] =", a[i], " "

const int MAXN = 500 * 1000 + 1;
vector<int> V[MAXN];
vector<int> dp[MAXN];
int main()
{
    int k, n;
    cin >> k >> n;

    dp[1].resize(n, 0);
    V[1].resize(n, 0);

    FOR(i, 2, k) {
        int n2; 
        cin >> n2;
        REP(j, n2) {
            int a;
            cin >> a;
            dp[i].push_back(0);
            V[i].push_back(a);
        }
    }
    int res = n;
    FORD(i, k, 1) {
        int sum = 0;
        REP(j, SIZ(V[i])) {
            debug(i, j);
            maxi(dp[i][j], 1);
            sum += dp[i][j];
            if(V[i][j] > 0)dp[i-1][V[i][j] - 1] += dp[i][j];
        }
        maxi(res, sum);
        debug(i, sum, dp[i]);
    }
    cout << res << endl;
}