#include<iostream> #include<string> #include<sstream> using namespace std; bool seventimes(int num){ if(num % 7 == 0) return true; else return false; } bool hadseven(int num){ stringstream trans; trans<<num; string numstr; trans>>numstr; if(numstr.find('7') != numstr.npos) return true; else return false; } int main(){ int n; cin>>n; int seven = 0; for(int i = 1; i < n+1; i++){ if(seventimes(i) || hadseven(i)){ seven++; } } cout<<seven<<endl; return 0; }