#include<iostream> // cin\cout\endl #include<cstdio> //scanf()\printf() #include<cstring> // strcpy()\strcat()\strcmp()\strlen()\memset() #include<cmath> //sqrt()\pow()\abs()\ceil()\floor()\max()\min() using namespace std; int main(){ long long n,s; cin>>n; s+=n; cin>>n; s+=n; cin>>n; s+=n; cin>>n; s+=n; cin>>n; s+=n; cin>>n; s+=n; cin>>n; s+=n; cout<<s/7; return 0; }