#include <bits/stdc++.h>
#include <ext/pb_ds/assoc_container.hpp> // Common file
#include <ext/pb_ds/tree_policy.hpp> // Including tree_order_statistics_node_update
#define IO ios_base::sync_with_stdio(0); cin.tie(0); cout.tie(0)

using namespace std;
using namespace __gnu_pbds;
using ll = long long;

template<typename key> using ordered_set = tree <key, null_type, less<key>, rb_tree_tag, tree_order_statistics_node_update>;

char arr[8][8];

bool checkRow(int r, int c) {
    for(int i = c + 1; i < 8; i++) {
        if(arr[r][i] == '*')
            return true;
    }
    return false;
}

bool checkCol(int r, int c) {
    for(int i = r + 1; i < 8; i++) {
        if(arr[i][c] == '*')
            return true;
    }
    return false;
}

bool checkDiag(int r, int c) {
    for(int i = r + 1, j = c + 1; i < 8 && j < 8; i++, j++) {
        if(arr[i][j] == '*') {
            return true;
        }
    }
    for(int i = r + 1, j = c - 1; i < 8 && j >= 0; i++, j--) {
        if(arr[i][j] == '*') {
            return true;
        }
    }
    for(int i = r - 1, j = c + 1; i >= 0 && j < 8; i--, j++) {
        if(arr[i][j] == '*') {
            return true;
        }
    }
    for(int i = r - 1, j = c - 1; i >= 0 && j >= 0; i--, j--) {
        if(arr[i][j] == '*') {
            return true;
        }
    }
    return false;
}

int main() {
    IO;
    for(int i = 0; i < 8; i++) {
        for(int j = 0; j < 8; j++)
            cin >> arr[i][j];
    }
    for(int i = 0; i < 8; i++) {
        for(int j = 0; j < 8; j++) {
            if(arr[i][j] == '*') {
                if(checkRow(i, j) || checkCol(i, j) || checkDiag(i, j)) {
                    return cout << "invalid", 0;
                }
            }
        }
    }
    cout << "valid";
    return 0;
}