#include <bits/stdc++.h>
#define _GLIBCXX_DEBUG
using namespace std;
using ll = long long;
using vec = vector<ll>;
using vect = vector<double>;
using Graph = vector<vector<ll>>;
#define loop(i, n) for (ll i = 0; i < n; i++)
#define Loop(i, m, n) for (ll i = m; i < n; i++)
#define pool(i, n) for (ll i = n; i >= 0; i--)
#define Pool(i, m, n) for (ll i = n; i >= m; i--)
#define mod 1000000007ll
//#define mod 998244353ll
#define flagcount __builtin_popcount
#define flag(x) (1ll << x)
#define flagadd(bit, x) bit |= flag(x)
#define flagpop(bit, x) bit &= ~flag(x)
#define flagon(bit, i) bit &flag(i)
#define flagoff(bit, i) !(bit & (1ll << i))
#define all(v) v.begin(), v.end()
#define low2way(v, x) lower_bound(all(v), x)
#define high2way(v, x) upper_bound(all(v), x)
#define idx_lower(v, x) (distance(v.begin(), low2way(v, x)))  //配列vでx未満の要素数を返す
#define idx_upper(v, x) (distance(v.begin(), high2way(v, x))) //配列vでx以下の要素数を返す
#define idx_lower2(v, x) (v.size() - idx_lower(v, x))         //配列vでx以上の要素数を返す
#define idx_upper2(v, x) (v.size() - idx_upper(v, x))         //配列vでxより大きい要素の数を返す
#define putout(a) cout << a << endl
#define Sum(v) accumulate(all(v), 0ll)
#define gcd(x, y) __gcd(x, y)
ll ctoi(char c)
{
    if (c >= '0' && c <= '9')
    {
        return c - '0';
    }
    return -1;
}
template <typename T>
string make_string(T N)
{
    string ret;
    T now = N;
    while (now > 0)
    {
        T x = now % 10;
        ret += (char)('0' + x);
        now /= 10;
    }
    reverse(all(ret));
    return ret;
}
template <typename T>
T lcm(T x, T y)
{
    T z = gcd(x, y);
    return x * y / z;
}
template <typename T>
bool primejudge(T n)
{
    if (n < 2)
        return false;
    else if (n == 2)
        return true;
    else if (n % 2 == 0)
        return false;
    double sqrtn = sqrt(n);
    for (T i = 3; i < sqrtn + 1; i++)
    {
        if (n % i == 0)
        {
            return false;
        }
        i++;
    }
    return true;
}
template <typename T>
bool chmax(T &a, const T &b)
{
    if (a < b)
    {
        a = b; // aをbで更新
        return true;
    }
    return false;
}
template <typename T>
bool chmin(T &a, const T &b)
{
    if (a > b)
    {
        a = b; // aをbで更新
        return true;
    }
    return false;
}
//場合によって使い分ける
//const ll dx[4]={1,0,-1,0};
//const ll dy[4]={0,1,0,-1};
const ll dx[8] = {1, 1, 0, -1, -1, -1, 0, 1};
const ll dy[8] = {0, 1, 1, 1, 0, -1, -1, -1};
//2次元配列の宣言
//vector<vector<ll>> field(h, vector<ll>(w));

int main()
{
    cout << fixed << setprecision(30);
    ll N, M;
    cin >> N >> M;
    vector<bool> available(M + 1, true); //実施されるかどうか
    vector<vector<ll>> A(N, vector<ll>(M));
    loop(i, N) loop(j, M) cin >> A[i][j];
    ll ans = 1e9;
    loop(i, M)
    {
        vector<ll> count(M + 1); //各競技の参加者の数
        loop(j, N)
        {
            loop(k, M)
            {
                ll now = A[j][k];
                if (available[now])
                {
                    count[now]++;
                    break;
                }
            }
        }
        ll maxx = 0;
        Loop(j, 1, M + 1) if (available[j]) maxx = max(maxx, count[j]);
        Loop(j, 1, M + 1) if (available[j]) if (count[j] == maxx)
        {
            available[j] = false;
            break;
        }
        ans = min(ans, maxx);
    }
    putout(ans);
    return 0;
}

#include<bits/stdc++.h>
using namespace std;
#define Nitroboost  ios_base::sync_with_stdio(0);cin.tie(NULL);cout.tie(NULL)
#define ll long long int 
const int mod=1e9+7;
const int N=1e6+5;



int main()
    {
        Nitroboost;
        #ifndef ONLINE_JUDGE
        freopen("input.txt", "r", stdin);
        freopen("output.txt", "w", stdout);
        #endif

        int n,m;
        cin>>n>>m;
        map<int,int>mp;
        for(int i=1;i<=m;i++)
            mp[i]=i;

        multiset<int>v;
        for(int i=1;i<=m;i++)
            v.insert(0);

        for(int i=1;i<=n;i++)
        {
            int l,r;
            cin>>l>>r;
            r++;
            auto it=mp.lower_bound(l);
            int t=-1;
            while(it!=mp.end() && it->first<=r)
            {
                t=max(t,it->second);
                v.erase(v.find(it->first-it->second));
                mp.erase(it++);
            }
            if(t!=-1 && r<=m)
            {
                v.insert(r-t);
                mp[r]=t;
            }

            if(v.size()>0)
            cout<<i+(*v.begin())<<"\n";
            else
                cout<<"-1\n";
        }
    }
