Effect: $ n $ space station, reference numeral $ 1, ..., n $, $ 0 $ Earth, moon $ -1 $, $ m $ a ship, the ship can only $ I $ $ carrier $ H_i who periodically stops at the set $ S_i $, ship every movement takes time for the $ 1 $. the initial $ k $ individuals in the earth, seeking how to make $ k $ personal boat to full moon shortest time.
- recording $ I $ $ t $ space station status time $ (i, t) $.
To S $ $ $ (0,0) connected edge $ $ k $, $ (- 1, t) $ $ T $ connected to the side $ INF $, $ (i, t) $ to $ (i, t + 1 ) $ edges even $ INF $.
Enumeration time, every time the spacecraft will be transferred into the internal network of Tim, if the maximum current flow is $ k $, you can reach.
#include <iostream>
#include <sstream>
#include <algorithm>
#include <cstdio>
#include <math.h>
#include <set>
#include <map>
#include <queue>
#include <string>
#include <string.h>
#include <bitset>
#include <unordered_map>
#define REP(i,a,n) for(int i=a;i<=n;++i)
#define PER(i,a,n) for(int i=n;i>=a;--i)
#define hr putchar(10)
#define pb push_back
#define lc (o<<1)
#define rc (lc|1)
#define mid ((l+r)>>1)
#define ls lc,l,mid
#define rs rc,mid+1,r
#define x first
#define y second
#define io std::ios::sync_with_stdio(false)
#define endl '\n'
#define DB(a) ({REP(__i,1,n) cout<<a[__i]<<' ';hr;})
using namespace std;
typedef long long ll;
typedef pair<int,int> pii;
const int P = 1e9+7, P2 = 998244353, INF = 0x3f3f3f3f;
ll gcd(ll a,ll b) {return b?gcd(b,a%b):a;}
ll qpow(ll a,ll n) {ll r=1%P;for (a%=P;n;a=a*a%P,n>>=1)if(n&1)r=r*a%P;return r;}
ll inv(ll x){return x<=1?1:inv(P%x)*(P-P/x)%P;}
inline int rd() {int x=0;char p=getchar();while(p<'0'||p>'9')p=getchar();while(p>='0'&&p<='9')x=x*10+p-'0',p=getchar();return x;}
//head
const int N = 1e6+10;
int n, m, k, S, T, tot;
int h[N], r[N], fa[N];
vector<int> g[N];
struct edge {
int v,w,next;
} e[N];
int head[N], dep[N], vis[N], cur[N], cnt=1;
queue<int> Q;
void add(int u, int v, int w) {
e[++cnt] = {v,w,head[u]};
head[u] = cnt;
e[++cnt] = {u,0,head[v]};
head[v] = cnt;
}
int bfs() {
REP(i,1,tot) dep[i]=INF,vis[i]=0,cur[i]=head[i];
dep[S]=0,Q.push(S);
while (Q.size()) {
int u = Q.front(); Q.pop();
for (int i=head[u]; i; i=e[i].next) {
if (dep[e[i].v]>dep[u]+1&&e[i].w) {
dep[e[i].v]=dep[u]+1;
Q.push(e[i].v);
}
}
}
return dep[T]!=INF;
}
int dfs(int x, int w) {
if (x==T) return w;
int used = 0;
for (int i=cur[x]; i; i=e[i].next) {
cur[x] = i;
if (dep[e[i].v]==dep[x]+1&&e[i].w) {
int flow = dfs(e[i].v,min(w-used,e[i].w));
if (flow) {
used += flow;
e[i].w -= flow;
e[i^1].w += flow;
if (used==w) break;
}
}
}
return used;
}
int dinic() {
int ans = 0;
while (bfs()) ans+=dfs(S,INF);
return ans;
}
int Find(int x) {return fa[x]?fa[x]=Find(fa[x]):x;}
void add(int x, int y) {
x = Find(x), y = Find(y);
if (x!=y) fa[x] = y;
}
map<pii,int> s;
int id(int x, int y) {
if (s.count(pii(x,y))) return s[pii(x,y)];
return s[pii(x,y)]=++tot;
}
int main() {
scanf("%d%d%d", &n, &m, &k);
REP(i,1,m) {
scanf("%d%d", h+i, r+i);
REP(j,1,r[i]) {
int x;
scanf("%d", &x);
g[i].pb(x);
add(g[i].front()+2,g[i].back()+2);
}
if (r[i]==1) g[i].clear(),--i,--m;
}
if (Find(1)!=Find(2)) return puts("0"),0;
int mf = 0;
S = ++tot, T = ++tot;
add(S,id(0,0),k);
for (int t=1; ; ++t) {
add(id(0,t-1),id(0,t),INF);
REP(i,1,n) {
add(id(i,t-1),id(i,t),INF);
}
REP(i,1,m) {
int L = id(g[i][(t%r[i]-1+r[i])%r[i]],t-1), R = id(g[i][t%r[i]],t);
add(L,R,h[i]);
}
add(id(-1,t),T,INF);
if ((mf+=dinic())==k) return printf("%d\n",t),0;
}
}