#include<iostream>
#include<algorithm>
#include<string>
#include<queue>
#include<stack>
using namespace std;
typedef long long ll;
const int N=1e3;
ll c[N];
int dx[4]={-1,1,0,0};
int dy[4]={0,0,-1,1};
ll a[N]={0};
ll n;
ll k=0;
int mp[10005][10005];
bool vis[1000][1000];
struct node{
int x,y;
}l,r;
bool check(int h){
ll ans=0;
ll con=0;
for(int i=n;i>=1;i--){
if(c[i]<h){
ans+=(h-c[i]);
if(h-c[i]>k)return false;
con++;
}else{
con++;
}
}
}
int main(){
cin>>n;
if(n==2){
cin>>a[1];
cout<<n+a[1]<<endl;
}
}