#include <bits/stdc++.h>
using namespace std;
void canhazfast() {
  ios_base::sync_with_stdio(false);
  cin.tie(nullptr);
  cout.tie(nullptr);
}
template <typename T>
T gcd(T a, T b) {
  return b ? gcd(b, a % b) : a;
}
template <typename T>
T extgcd(T a, T b, T &x, T &y) {
  T x0 = 1, y0 = 0, x1 = 0, y1 = 1;
  while (b) {
    T q = a / b;
    a %= b;
    swap(a, b);
    x0 -= q * x1;
    swap(x0, x1);
    y0 -= q * y1;
    swap(y0, y1);
  }
  x = x0;
  y = y0;
  return a;
}
int ctz(unsigned x) { return __builtin_ctz(x); }
int ctzll(unsigned long long x) { return __builtin_ctzll(x); }
int clz(unsigned x) { return __builtin_clz(x); }
int clzll(unsigned long long x) { return __builtin_clzll(x); }
int popcnt(unsigned x) { return __builtin_popcount(x); }
int popcntll(unsigned long long x) { return __builtin_popcountll(x); }
int bsr(unsigned x) { return 31 ^ clz(x); }
int bsrll(unsigned long long x) { return 63 ^ clzll(x); }
double dp[100];
int lad[100];
int conv(int r, int c) { return 10 * r + (r & 1 ? 9 - c : c); }
int main() {
  constexpr int n = 10, nn = 100;
  for (int i = 0; i < n; ++i) {
    for (int j = 0; j < n; ++j) {
      int h, u;
      scanf("%d", &h);
      u = conv(i, j);
      lad[u] = h ? conv(i - h, j) : u;
    }
  }
  for (int i = 1; i < 6; ++i) dp[i] = 6.0;
  for (int i = 6; i < nn; ++i) {
    for (int j = 1; j <= 6; ++j) dp[i] += min(dp[i - j], dp[lad[i - j]]);
    dp[i] = dp[i] / 6.0 + 1.0;
  }
  printf("%.12f\n", dp[nn - 1]);
  return 0;
}
