# include <iostream>
# include <fstream>
using namespace std;

int n, a[100], b[100], x, y, nr=0;
int main()
{
    ifstream fin("fractii.in");
    ofstream fout("fractii.out");
    fin>>n;
    for(int i=0; i<n; i++)
    {
        a[0]=1;
        a[i]=a[i-1]+1;
    }
    for(int j=0; j<n; j++)
    {
        b[0]=1;
        b[j]=b[j-1]+1;
    }
    for(int i=0; i<n; i++)
    {
        x=a[i];
        for(int j=0; j<n; i++)
            y=b[j];
        while(x!=y)
        {
            if(x>y)
                x-=y;
            else
                y-=x;
        }
        if(x==1)
            nr++;
    }
    fout<<nr;
    return 0;
}