#include <bits/stdc++.h>

using namespace std;


int main(){
    int i,j,k,c,x,n;
    cin>>n>>k>>x;
    int a[n];
    a[0] = 1;
   x = a[n-1];
    
    for(i=0;i<j;i++){
     for(j=n-1;j>i;j--){
     if(a[i]!=a[i+1]){
      c=0;
     }else
             c++;
      if(a[j]!=a[j-1]){
            c=0;  
         }
         else
             c++; 
     }
    
    }
  cout<<n-1;



return 0;
}