#include <iostream>
#include <sstream>
#include <cstdio>
#include <cstdlib>
#include <cmath>
#include <ctime>
#include <cstring>
#include <string>
#include <vector>
#include <stack>
#include <queue>
#include <deque>
#include <map>
#include <set>
#include <bitset>
#include <numeric>
#include <utility>
#include <iomanip>
#include <algorithm>
#include <functional>
using namespace std;

typedef long long ll;
typedef vector<int> vint;
typedef vector<long long> vll;
typedef pair<int,int> pint;
typedef pair<long long, long long> pll;

#define MP make_pair
#define PB push_back
#define ALL(s) (s).begin(),(s).end()
#define EACH(i, s) for (__typeof__((s).begin()) i = (s).begin(); i != (s).end(); ++i)
#define COUT(x) cout << #x << " = " << (x) << " (L" << __LINE__ << ")" << endl

template<class T> inline bool chmax(T& a, T b) { if (a < b) { a = b; return 1; } return 0; }
template<class T> inline bool chmin(T& a, T b) { if (a > b) { a = b; return 1; } return 0; }
template<class T1, class T2> ostream& operator << (ostream &s, pair<T1,T2> P) 
{ return s << '<' << P.first << ", " << P.second << '>'; }
template<class T> ostream& operator << (ostream &s, vector<T> P) 
{ for (int i = 0; i < P.size(); ++i) { if (i > 0) { s << " "; } s << P[i]; } return s; }
template<class T> ostream& operator << (ostream &s, vector<vector<T> > P) 
{ for (int i = 0; i < P.size(); ++i) { s << endl << P[i]; } return s << endl; }
template<class T1, class T2> ostream& operator << (ostream &s, map<T1,T2> P) 
{ EACH(it, P) { s << "<" << it->first << "->" << it->second << "> "; } return s; }




pint list[10] = {
    pint(0, 1), pint(1, 2), pint(2, 3), pint(4, 5), pint(5, 6), pint(6, 7), pint(0, 4), pint(1, 5), pint(2, 6), pint(3, 7)
};

int main() {
    //freopen( "/Users/macuser/Dropbox/Contest/input.in", "r", stdin );
    vint start(8);
    vint goal(8);
    for (int i = 0; i < 8; ++i) goal[i] = i;
    

        queue<vint> que;
        que.push(goal);
        map<vint,int> ma;
        ma[goal] = 0;
        
        while (!que.empty()) {
            vint vec = que.front(); que.pop();
            int dis = ma[vec];
            
            for (int i = 0; i < 10; ++i) {
                if (vec[list[i].first] != 0 && vec[list[i].second] != 0) continue;

                swap(vec[list[i].first], vec[list[i].second]);
                if (!ma.count(vec)) {
                    ma[vec] = dis + 1;
                    que.push(vec);
                }
                swap(vec[list[i].first], vec[list[i].second]);
            }
        }
        
    while (cin >> start[0]) {
        for (int i = 1; i < 8; ++i) cin >> start[i];
        cout << ma[start] << endl;
    }
    return 0;
}
