#include<bits/stdc++.h> using namespace std; int n,ans; int main(){ cin>>n; n*=100; for(int i5=1;i5<=n/5;i5++){ for(int i2=1;i2<=(n-i5*5)/2;i2++){ if(i5*5+i2*2<n) ans++; } } cout<<ans<<endl; return 0; }