#include <bits/stdc++.h>
using namespace std;
#ifdef DEBUG
#include "../Library/debug.h"
#else
#include "september.h"
#define dbg(x...)
#endif
typedef long long ll;
typedef long double ld;
typedef pair<int, int> pi;
typedef pair<ll, ll> pl;
typedef vector<int> vi;
typedef vector<bool> vb;
typedef vector<ll> vl;
typedef vector<pi> vpi;
typedef vector<pl> vpl;
#define FOR(i, a, b) for (int i = (a); i < (b); ++i)
#define F0R(i, a) for (int i = 0; i < (a); ++i)
#define FORd(i, a, b) for (int i = (b) - 1; i >= (a); --i)
#define F0Rd(i, a) for (int i = (a) - 1; i >= 0; --i)
#define trav(a, x) for (auto& a : x)
#define f first
#define s second
#define pb push_back
#define sz(x) (int)(x).size()
#define all(x) x.begin(), x.end()
const char nl = '\n';
const int INF = 1e9;
const ll MOD = 998244353;
const int mxN = 3e5+5;
int solve(int n,int m,vi p,vector<vi> s){
vector<vi> cnt(m,vi(n-1));
F0R(i,m){
vi vis(n),id(n);
F0R(j,n-1){
id[s[i][j]]=j;
}
int mn=n-1;
int c=0;
F0Rd(j,n-1){
// dbg(j,s[i][j],p[s[i][j]],vis[p[s[i][j]]])
if(p[s[i][j]]==0||vis[p[s[i][j]]]){
}
else{
mn=min(mn,id[p[s[i][j]]]);
vis[s[i][j]]=1;
}
cnt[i][j]=c;
if(j<=mn){
c++;
mn=j;
}
}
}
// dbg(cnt)
int ans=1;
vi c(n);
int _c=0;
F0R(i,n-2){
bool x=true;
F0R(j,m){
c[s[j][i]]++;
if(c[s[j][i]]==m)
_c++;
if(cnt[j][i]==cnt[j][i+1])
x=false;
}
if(x&&_c==(i+1))ans++;
}
return ans;
}
#ifdef DEBUG
int32_t main(){
ios::sync_with_stdio(false); cin.tie(NULL); cout.tie(NULL);
// cout<<solve(3,1,{-1,0,0},{{1,2}})<<nl;
// cout<<solve(5,2,{-1,0,0,1,1},{{1,2,3,4},{4,1,2,3}})<<nl;
int n,m;
cin>>n>>m;
vi p(n);
F0R(i,n)cin>>p[i];
vector<vi> a(m,vi(n-1));
F0R(i,m)F0R(j,n-1)cin>>a[i][j];
cout<<solve(n,m,p,a)<<endl;
}
#endif
