#include <bits/stdc++.h>
using namespace std;
typedef long long ll;
typedef long double ld;
typedef complex<ld> cd;
typedef pair<int, int> pi;
typedef pair<ll,ll> pl;
typedef pair<ld,ld> pd;
typedef pair<int, pi> pii;
typedef vector<int> vi;
typedef vector<ld> vd;
typedef vector<ll> vl;
typedef vector<pi> vpi;
typedef vector<pl> vpl;
typedef vector<cd> vcd;
#define fax(i, a) for (int i = 0; i < (a); i++)
#define f0x(i, a, b) for (int i = (a); i < (b); i++)
#define f0xd(i,a,b) for (int i = (b)-1; i >= (a); i--)
#define faxd(i,a) for (int i = (a)-1; i >= 0; i--)
#define trav(a, x) for (auto& a : x)
#define memeset memset
#define mp make_pair
#define pb push_back
#define f first
#define s second
#define lb lower_bound
#define ub upper_bound
#define sz(x) (int)x.size()
#define all(x) begin(x), end(x)
#define rsz resize
template<class T> void ckmin(T &a, T b) { a = min(a, b); }
template<class T> void ckmax(T &a, T b) { a = max(a, b); }
template <class T, int ...Ns> struct BIT {
T val = 0;
void upd(T v) { val += v; }
T query() { return val; }
};
template <class T, int N, int... Ns> struct BIT<T, N, Ns...> {
BIT<T,Ns...> bit[N + 1];
template<typename... Args> void upd(int pos, Args... args) {
for (; pos <= N; pos += (pos&-pos)) bit[pos].upd(args...);
}
template<typename... Args> T sum(int r, Args... args) {
T res = 0; for (; r; r -= (r&-r)) res += bit[r].query(args...);
return res;
}
template<typename... Args> T query(int l, int r, Args... args) {
return sum(r,args...)-sum(l-1,args...);
}
};
namespace input {
template<class T> void re(complex<T>& x);
template<class T1, class T2> void re(pair<T1,T2>& p);
template<class T> void re(vector<T>& a);
template<class T, size_t SZ> void re(array<T,SZ>& a);
template<class T> void re(T& x) { cin >> x; }
void re(double& x) { string t; re(t); x = stod(t); }
void re(ld& x) { string t; re(t); x = stold(t); }
template<class T, class... Ts> void re(T& t, Ts&... ts) {
re(t); re(ts...);
}
template<class T> void re(complex<T>& x) { T a,b; re(a,b); x = cd(a,b); }
template<class T1, class T2> void re(pair<T1,T2>& p) { re(p.f,p.s); }
template<class T> void re(vector<T>& a) { fax(i,sz(a)) re(a[i]); }
template<class T, size_t SZ> void re(array<T,SZ>& a) { fax(i,SZ) re(a[i]); }
}
using namespace input;
namespace output {
void pr(int x) { cout << x; }
void pr(long x) { cout << x; }
void pr(ll x) { cout << x; }
void pr(unsigned x) { cout << x; }
void pr(unsigned long x) { cout << x; }
void pr(unsigned long long x) { cout << x; }
void pr(float x) { cout << x; }
void pr(double x) { cout << x; }
void pr(ld x) { cout << x; }
void pr(char x) { cout << x; }
void pr(const char* x) { cout << x; }
void pr(const string& x) { cout << x; }
void pr(bool x) { pr(x ? "true" : "false"); }
template<class T1, class T2> void pr(const pair<T1,T2>& x);
template<class T> void pr(const T& x);
template<class T, class... Ts> void pr(const T& t, const Ts&... ts) {
pr(t); pr(ts...);
}
template<class T1, class T2> void pr(const pair<T1,T2>& x) {
pr("{",x.f,", ",x.s,"}");
}
template<class T> void pr(const T& x) {
pr("{"); // const iterator needed for vector<bool>
bool fst = 1; for (const auto& a: x) pr(!fst?", ":"",a), fst = 0;
pr("}");
}
void ps() { pr("\n"); } // print w/ spaces
template<class T, class... Ts> void ps(const T& t, const Ts&... ts) {
pr(t); if (sizeof...(ts)) pr(" "); ps(ts...);
}
void pc() { pr("]\n"); } // debug w/ commas
template<class T, class... Ts> void pc(const T& t, const Ts&... ts) {
pr(t); if (sizeof...(ts)) pr(", "); pc(ts...);
}
#define dbg(x...) pr("[",#x,"] = ["), pc(x);
}
using namespace output;
namespace io {
void setIn(string s) { freopen(s.c_str(),"r",stdin); }
void setOut(string s) { freopen(s.c_str(),"w",stdout); }
void setIO(string s = "") {
ios_base::sync_with_stdio(0); cin.tie(0); // fast I/O
if (sz(s)) { setIn(s+".in"), setOut(s+".out"); } // for USACO
}
}
using namespace io;
mt19937 rnd(chrono::high_resolution_clock::now().time_since_epoch().count());
const int MOD = 1000000007; // 998244353
const ll INF = 1e18;
const int MX = 500;
const ld PI = 4*atan((ld)1);
const int WIN = 1, LOSE = 2;
vector<pii> rev[MX][MX][2]; int deg[MX], cnt[MX][MX]; pii go[MX][MX][2]; int gst[MX][MX][2];
int ret = -1;
int start(int N, bool A[MX][MX]){
fax(i, N) fax(j, N) gst[i][j][0] = gst[i][j][1] = LOSE;
fax(i, N) {
fax(j, N){
deg[i] += A[i][j];
}
}
queue<pii> st;
fax(i, N) {
gst[i][i][0] = gst[i][i][1] = WIN;
st.push(mp(i, mp(i, 0)));
st.push(mp(i, mp(i, 1)));
}
while(!st.empty()) {
pii curr = st.front(); st.pop();
if(gst[curr.f][curr.s.f][curr.s.s] == WIN){
fax(i, N){
if(curr.s.s == 1 && (A[curr.f][i] || i == curr.f)){
pii to = mp(i, mp(curr.s.f, 0));
if(gst[to.f][to.s.f][to.s.s] == WIN) continue;
go[to.f][to.s.f][to.s.s] = mp(curr.f, mp(curr.s.f, curr.s.s));
gst[to.f][to.s.f][to.s.s] = WIN;
st.push(mp(to.f, mp(to.s.f, to.s.s)));
}
if(curr.s.s == 0 && A[curr.s.f][i]){
pii to = mp(curr.f, mp(i, 1));
if(gst[to.f][to.s.f][to.s.s] == WIN) continue;
cnt[to.f][to.s.f]++;
if(cnt[to.f][to.s.f] == deg[to.s.f]){
gst[to.f][to.s.f][to.s.s] = WIN;
go[to.f][to.s.f][to.s.s] = mp(curr.f, mp(curr.s.f, curr.s.s));
st.push(mp(to.f, mp(to.s.f, to.s.s)));
}
}
}
}
}
fax(i, N){
fax(j, N){
if(gst[i][j][0] != WIN){
break;
}
if(j == N - 1){
ret = i;
}
}
}
return ret;
}
int nextMove(int R){
// dbg(go[ret][R][0]);
return ret = go[ret][R][0].f;
}
/*
int main() {
setIO();
int N; re(N);
bool inp[MX][MX];
fax(i, N){
fax(j, N){
re(inp[i][j]);
}
}
ps(start(N, inp));
cout << endl;
int r; re(r);
while(r != -1){
ps(nextMove(r));
cout << endl;
re(r);
}
}
*/
