#include <bits/stdc++.h>   using namespace std;   char a[100][1000] = {0};   int main() {     ios_base::sync_with_stdio(false);     cin.tie(0);     long long int t;     cin >> t;     while (t--) {       long long int n, m, x, y;       cin >> n >> m >> x >> y;       for (long long int i = 1; i <= n; i++) {         for (long long int j = 1; j <= m; j++) {           cin >> a[i][j];         }       }       long long int ans = 0;       for (long long int i = 1; i <= n; i++) {         for (long long int j = 1; j <= m; j++) {           if (a[i][j] ==  . ) {             long long int pos = j;             for (long long int k = j; k <= m; k++) {               if (a[i][k] ==  . ) {                 pos = k;               } else {                 break;               }             }             long long int temp = pos - j + 1;             ans += min(temp * x, (temp / 2) * y + x * (temp % 2 == 1));             j = pos;           }         }       }       cout << ans << endl;     }     return 0;   }   