#include <bits/stdc++.h>
#pragma GCC optimize ("O2")
#define endl '\n'
#define fr first
#define sc second
#define vc vector<int>
using namespace std;
int32_t main() {
ios_base::sync_with_stdio(0);
cin.tie(0); cout.tie(0);
cout.setf(ios::fixed);
cout.precision(0);
int r, c, d, k;
cin >> r >> c >> d >> k;
if(r == 1){
char arr[c+1];
vc h, a;
for(int i = 1; i <= c; i++){
cin >> arr[i];
if(arr[i] == 'M') h.push_back(i);
if(arr[i] == 'S') a.push_back(i);
}
int cont = 0;
for(int i = 0; i < h.size(); i++){
int c = 0;
for(int j = 0; j < a.size(); j++){
if(abs(h[i] - a[j]) <= d) c++;
}
if(c >= k) cont++;
}
cout << cont << endl;
}else{
char arr[r+1][c+1];
vector<pair<int, int>> h, a;
for(int i = 1; i <= r; i++){
for(int j= 1 ;j <= c; j++){
cin >> arr[i][j];
if(arr[i][j] == 'M') h.push_back({i,j});
if(arr[i][j] == 'S') a.push_back({i,j});
}
}
vc hon(h.size(), 0);
int cont = 0;
for(int i = 0; i < h.size(); i++){
int c = 0;
for(int j = 0; j < a.size(); j++){
if((max(abs(h[i].fr - a[j].fr), abs(h[i].sc - a[j].sc))) <= d) c++;
}
if(c >= k) cont++;
}
cout << cont << endl;
}
return 0;
}
