Codeforces 110A Nearly Lucky Number Solution in CPP

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Codeforces 110A Nearly Lucky Number solution in CPP

#include<bits/stdc++.h>
using namespace std;
int main()
{
    string a;
    int c=0,z=0;

    cin>>a;
    for(int i=0;i<a.size();i++) {
        if(a[i]=='4'||a[i]=='7')//Codeforces 110A Nearly Lucky Number solution in CPP
            c++;

}
if(c==4||c==7)
  cout<<"YES"<<endl;
  else
      cout<<"NO"<<endl;
}

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