B.cpp

#include<bits/stdc++.h>
using namespace std;
#define ll long long
#define ld long double
typedef unsigned long long ull;
#define loop(i,a,b) for(ll i=a;i<b;i++)
#define f(i,a,b) for(ll i=a;i<=b;i++)
#define testcases ll t;cin>>t;while(t--)
#define dec(x) greater<x>()

/*** Define Values ***/
#define mx 200005
#define mod 1000000007
#define PI acos(-1.0)
#define eps 1e-7
#define size1 100005

#define pb push_back
#define ff first
#define ss second
#define mp make_pair
#define mem(name, value) memset(name, value, sizeof(name))

/*** STLs ***/
typedef vector <ll> vll;
typedef set <ll> sll;
typedef multiset <ll> msll;
typedef queue <ll> qll;
typedef map <ll, ll> mll;
typedef pair <ll, ll> pll;
typedef vector <pair <ll , ll> > vpll;

/*** Sorts ***/
#define all(v) (v).begin(), (v).end()
#define rev(v) reverse(all(v))
#define srt(v) sort(all(v))
#define srtGreat(v) sort(all(v), greater<ll>())
inline bool cmp(pll a,pll b){ if(a.ff == b.ff)return a.ss < b.ss; return a.ff > b.ff; }

#define en cout << '\n';
#define no cout << "NO" << '\n'
#define yes cout << "YES" << '\n'
#define case cout << "Case " << t++ << ": "

/*** Functions
ll BigMod(ll base, ll pow, ll modvalue){ if (pow == 0) return 1;  ll ans = BigMod(base, pow / 2, modvalue);ll total = ((ans % modvalue) * (ans % modvalue)) % modvalue;  if(pow % 2 == 0) return total; else{ return (total * (base % modvalue) ) % modvalue; } }
ll InverseMod(ll base, ll pow) { if(pow == 0) return 1; ll ans = InverseMod(base, pow / 2); ans = (ans * ans) % mod; if(pow & 1){ return (ans * base) % mod; } else{ return ans; } }
bool checkprime(ll num) { if(num < 2) return false; for(ll i = 2; i * i <= num; i++){ if(num % i == 0) return false; } return true; }
ll EularPHI(ll num) { double ans = num; for(ll i = 2; i * i <= num; i++){ if(num % i == 0){ while (num % i == 0) { num /= i; } ans *= (1.0 - (1.0 / (double)i)); } } if(num > 1) ans *= (1.0 - (1.0 / (double)num)); return (ll)ans; }
ll sumofdigit(long ll n){ll sum=0;while(n){sum=sum+n%10;n=n/10;}return sum;}
ll countDigit(ll n) { if (n == 0) return 0; return 1 + countDigit(n / 10); }
ll countDigit(ll n) { return floor(log10(n) + 1); } //only positive  
 ***/

template <class T> inline T gcd(T a,T b){if(b == 0)return a; return gcd(b, a % b);}
template <class T> inline T lcm(T a,T b){return a * b / gcd<T>(a, b);}
template <class T> inline T power(T b,T p){ll ans = 1;while(p--) ans *= b; return ans;}

int main()
{

	#ifndef ONLINE_JUDGE
	freopen("C:/Users/91731/Documents/input.txt","r",stdin);
	freopen("C:/Users/91731/Documents/output.txt","w",stdout);
	freopen("C:/Users/91731/Documents/error.txt","w",stderr);
    #endif
	
	ios_base::sync_with_stdio(0); cin.tie(0); cout.tie(0);

	testcases
	{
		ll n,m,x,y;
		cin>>n>>m>>x>>y;
		ll star=0,dot=0,total=0;
		char s[n][m];
		char c;
		ll ans=0,count=0;
		loop(i,0,n)
		{
			count=0;
			loop(j,0,m)
			{
				cin>>c;
				if(c=='.')count++;
				else
				{
					ans+=min(x*(count%2)+y*(count/2),x*count);
					count=0;
				}
			}
			if(count>0)ans+=min(x*(count%2)+y*(count/2),x*count);
		}

		cout<<ans<<endl;
	
	
	
	}
}