#include <iostream>

 #include<cstdio>

 #include<cstring>

 #include<algorithm>

 #include<stdlib.h>

 #include<vector>

 using namespace std;

 vector<int>ed[];

 int a[][],vis[],de[];

 void dfs(int u)

 {

     int i;

     for(i =  ; i < (int)ed[u].size() ; i++)

     {

         int v = ed[u][i];

         if(!vis[v])

         {

             vis[v] = ;

             dfs(v);

         }

     }

 }

 int main()

 {

     int i,j,n,m;

     int num=;

     scanf("%d%d",&n,&m);

     for(i =  ; i <= n ;i++)

         for(j = ; j <= m ; j++)

         {

             scanf("%d",&a[i][j]);

             if(a[i][j]!=i)

             {

                 num++;

                 de[i]++;

                 ed[i].push_back(a[i][j]);

                 ed[a[i][j]].push_back(i);

             }

         }

     int sum=;

     for(i = ; i <= n ; i++)

     {

         if(de[i]&&!vis[i])

         {

             sum++;

             vis[i] = ;

             dfs(i);

         }

     }

     if(sum==)

     printf("0\n");

     else

     printf("%d\n",sum-+num);

     return ;

 }