tj

#include<bits/stdc++.h>
using namespace std;

int main()
{
    int a;
    int b = 1,c = 1;
    cin>>a;
    for(int i = 2;i<a;i++)
        {
            if(b>c)
                c+=b;
            else
                b+=c;
        }
    cout<<max(b,c);
}