This submission is migrated from previous version of oj.uz, which used different machine for grading. This submission may have different result if resubmitted.
#include <iostream>
#include <vector>
#include <algorithm>
using namespace std;
struct point{int x; int y; int z;};
bool cmpx(point a, point b) {return a.x<b.x;}
bool cmpy(point a, point b) {return a.y<b.y;}
int map[4][305000];
int arr[305000], ans[300500], ytoz[300500];
vector<int> elem[805000];
int* maxtree[800500];
point p[300500];
void init(int s, int e, int node){
  if(s==e) elem[node].push_back(ytoz[s]);
  else{
    int mid = (s+e)/2;
    init(s, mid, node*2);
    init(mid+1, e, node*2+1);
    int pt1 = 0, pt2 = 0;
    
    
    while(pt1<elem[node*2].size()&&pt2<elem[node*2+1].size()){
      if(elem[node*2][pt1]<elem[node*2+1][pt2]) elem[node].push_back(elem[node*2][pt1++]);
      else if(elem[node*2][pt1]>elem[node*2+1][pt2]) elem[node].push_back(elem[node*2+1][pt2++]);
      else{
        elem[node].push_back(elem[node*2][pt1++]);
        pt2++;
      }
    }
    for(int i=pt1; i<elem[node*2].size(); i++) elem[node].push_back(elem[node*2][i]);
    for(int i=pt2; i<elem[node*2+1].size(); i++) elem[node].push_back(elem[node*2+1][i]);
    
    
  }
}
void insert_node(int pos, int val, int s, int e, int node, int nodez){
  if(pos<s||pos>e) return;
  maxtree[node][nodez] = (maxtree[node][nodez]<val)?val:maxtree[node][nodez];
  if(s!=e){
    insert_node(pos, val, s, (s+e)/2, node, nodez*2);
    insert_node(pos, val, (s+e)/2+1, e, node, nodez*2+1);
  }
}
void insert(int y, int z, int val, int s, int e, int node, int m){
  if(y<s||y>e) return;
  int coord = lower_bound(elem[node].begin(), elem[node].end(), z)-elem[node].begin()+1;
  insert_node(coord, val, 1, elem[node].size(), node, 1);
  if(s!=e){
    insert(y,z,val,s,(s+e)/2,node*2,m);
    insert(y,z,val,(s+e)/2+1,e,node*2+1,m);
  }
}
int getmax_node(int z1, int z2, int s, int e, int node, int nodez){
  if(e<z1||s>z2) return 0;
  else if(z1<=s&&e<=z2) return maxtree[node][nodez];
  else{
    int a = getmax_node(z1, z2, s, (s+e)/2, node, nodez*2);
    int b = getmax_node(z1, z2, (s+e)/2+1, e, node, nodez*2+1);
    return a<b?b:a;
  }
}
int getmax(int y1, int y2, int z1, int z2, int s, int e, int node, int m){
  int c1 = lower_bound(elem[node].begin(), elem[node].end(), z1)-elem[node].begin()+1;
  int c2 = upper_bound(elem[node].begin(), elem[node].end(), z2)-elem[node].begin();
  if(e<y1||s>y2||c1>c2) return 0;
  else if(y1<=s&&e<=y2) return getmax_node(c1, c2, 1, elem[node].size(), node, 1);
  else{
    int a = getmax(y1, y2, z1, z2, s, (s+e)/2, node*2, m);
    int b = getmax(y1, y2, z1, z2, (s+e)/2+1, e, node*2+1, m);
    return a>b?a:b;
  }
}
int main() {
  int n,m;
  cin.sync_with_stdio(false);
  cin.tie(nullptr);
  cout.tie(nullptr);
  cin>>n>>m;
  for(int i=1; i<=n; i++){
    for(int j=1; j<=m; j++){
      
      cin>>arr[j];
      //arr[j] = j;
      map[i][j] = arr[j];
    
    }
    sort(arr+1, arr+m+1);
    for(int j=1; j<=m; j++){
      map[i][j] = lower_bound(arr+1, arr+m+1, map[i][j])-arr;
    }
  }
  for(int j=1; j<=m; j++) {
    
    p[j].x = map[1][j]; p[j].y = map[2][j]; p[j].z = (n==2)?1:map[3][j];
    ytoz[p[j].y] = p[j].z;
    
  }
  sort(p+1, p+m+1, cmpx);
  
  init(1, m, 1);
  
  for(int i=1; i<=4*m; i++){
    if(elem[i].size()!=0) maxtree[i] = new int[elem[i].size()*4+4]; 
  }
  
  int ans = -123;
  for(int i=1; i<=m; i++){
    int t = getmax(1, p[i].y, 1, p[i].z, 1, m, 1, m)+1;
    if(ans<t) ans = t;
    //cout<<t<<" ";
    insert(p[i].y, p[i].z, t, 1, m, 1, m);
  
  }
  cout<<ans;
}
Compilation message (stderr)
matrix.cpp: In function 'void init(int, int, int)':
matrix.cpp:25:14: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   25 |     while(pt1<elem[node*2].size()&&pt2<elem[node*2+1].size()){
      |           ~~~^~~~~~~~~~~~~~~~~~~~
matrix.cpp:25:39: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   25 |     while(pt1<elem[node*2].size()&&pt2<elem[node*2+1].size()){
      |                                    ~~~^~~~~~~~~~~~~~~~~~~~~~
matrix.cpp:38:21: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   38 |     for(int i=pt1; i<elem[node*2].size(); i++) elem[node].push_back(elem[node*2][i]);
      |                    ~^~~~~~~~~~~~~~~~~~~~
matrix.cpp:39:21: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   39 |     for(int i=pt2; i<elem[node*2+1].size(); i++) elem[node].push_back(elem[node*2+1][i]);
      |                    ~^~~~~~~~~~~~~~~~~~~~~~| # | Verdict  | Execution time | Memory | Grader output | 
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