// By ObeliX
#include <bits/stdc++.h>
#pragma GCC target( "sse,sse2,sse3,ssse3,sse4,popcnt,abm,mmx,avx,tune=native")
#pragma GCC optimize("Ofast,no-stack-protector,unroll-loops,fast-math,O3")
#include <unordered_map>
#include <cstddef>
#include <cassert>
#include <bitset>
#include <algorithm>
#include <iostream>
#include <iomanip>
#include <cmath>
#include <queue>
#include <map>
#include <set>
using namespace std;
const long long N = 1e6 + 5;
const long long MOD = 1e7 + 7;
const long long inf = 1e18;
long long n , m , d , k;
int main(){
//freopen( "cinema.in" , "r" , stdin );
//freopen( "cinema.out" , "w" , stdout );
ios_base::sync_with_stdio(0);
cin.tie(0);
cout.tie(0);
cin >> n >> m >> d >> k;
char c[n+5][m+5];
for ( int i = 0 ; i <= n + 1 ; i++ ) {
for ( int j = 0 ; j <= m + 1 ; j++ ) {
c[i][j] = '.';
}
}
long long cnt1 = 0 , cnt2 = 0;
for ( int i = 1 ; i <= n ; i++ ) {
for ( int j = 1 ; j <= m ; j++ ) {
cin >> c[i][j];
if ( c[i][j] == 'S' ) {
cnt1++;
}
if ( c[i][j] == 'M' ) {
cnt2++;
}
}
}
if ( d == max( n , m ) && cnt1 >= k ) {
cout << cnt2 ;
}
else {
if ( d == 1 && k == 1 ) {
long long ans = 0;
for ( int i = 1 ; i <= n ; i++ ) {
for ( int j = 1 ; j <= m ; j++ ) {
if ( c[i][j] == 'M' ) {
if ( c[i][j-1] == 'S' || c[i-1][j] == 'S' || c[i+1][j] == 'S' || c[i][j+1] == 'S' ||c[i+1][j-1] == 'S' ||c[i-1][j+1] == 'S' ||c[i-1][j-1] == 'S' ||c[i+1][j+1] == 'S') {
ans++;
}
}
}
}
cout << ans;
}
else {
if ( n == 1 ) {
long long scan[m+5];
for ( int i = 0 ; i <= m ; i++ ) {
scan[i] = 0;
}
for ( int i = 1 ; i <= m ; i++ ) {
if ( c[1][i] == 'S' ) {
scan[min( m + 1 , i + d + 1 )]--;
scan[max( 1ll , i - d )]++;
}
}
long long ans = 0;
for ( int i = 1 ; i <= m ; i++ ) {
scan[i] += scan[i-1];
if ( c[1][i] == 'M' && scan[i] >= k ) {
ans++;
}
}
cout << ans;
}
else {
vector <pair<long long , long long>> v1 , v2;
for ( int i = 1 ; i <= n ; i++ ) {
for ( int j = 1 ; j <= m ; j++ ) {
if ( c[i][j] == 'M' ) {
v2.push_back( { i , j } );
}
else if ( c[i][j] == 'S' ) {
v1.push_back( { i , j } );
}
}
}
long long ans = 0;
for ( auto it : v2 ) {
long long x = it.first , y = it.second;
long long cnt = 0;
for ( auto it1 : v1 ) {
long long x1 = it1.first , y1 = it1.second;
if ( max( abs( x - x1 ) , abs( y1 - y ) ) <= d ) {
cnt++;
}
}
if ( cnt >= k ) {
ans++;
}
}
cout << ans ;
}
}
}
}
