#include<iostream>

int main(){
    std::string s; std::cin >> s;
    int diff=1e4;
    for(int i=0; i<s.size()-2; ++i){
        int num=std::stoi(s.substr(i,3));
        num = std::abs(num-753);
        diff = std::min(diff,num);
    }
    std::cout << diff << std::endl;
    return 0;
}
#include<iostream>
#include<iomanip>
#include<cmath>
#include<string>
#include<vector>
#include<list>
#include<algorithm>
#include<map>
#include<set>
#include<queue>
#include<stack>
using namespace std;
typedef long long ll;
#define fi first
#define se second
#define mp make_pair
#define rep(i, n) for(int i=0;i<n;++i)
#define rrep(i, n) for(int i=n;i>=0;--i)
const int inf=1e9+7;
const ll mod=1e9+7;
const ll big=1e18;
const double PI=2*asin(1);

int main() {
  int N;
  cin>>N;
  cout<<N/3<<endl;
}

