#include <iostream>
#include <iomanip>
#include <math.h>
#include <algorithm>
#include <string>

using namespace std;
#define ll long long
#define F first
#define S second
#define PB push_back
#define MP make_pair


int main()
{
    int c=0 , w=0;
  string n ; cin>>n ;

  for(int i =0 ; i<n.length();i++)
   {

       if(n[i]=='7')
            c++;
        else
            w++;

   }cout<<((c==1)?"Yes":"No");



}
