#include <bits/stdc++.h>
using namespace std;
int main() {
ios_base::sync_with_stdio(false);
cin.tie(nullptr);
int r, c, n;
cin >> r >> c >> n;
int sx, sy, gx, gy; cin >> sx >> sy >> gx >> gy; sx--; sy--; gx--; gy--;
vector<vector<bool>> grid(r, vector<bool>(c));
for (int i = 0; i < r; i++) {
string s; cin >> s;
for (int j = 0; j < c; j++) grid[i][j] = s[j] == '.';
}
vector<vector<int>> dist(r, vector<int>(c, INT_MAX));
priority_queue<array<int, 3>, vector<array<int, 3>>, greater<array<int, 3>>> pq;
dist[sx][sy] = 0;
pq.push({0, sx, sy});
const pair<int, int> dir[4] = {
{1, 0},
{-1, 0},
{0, 1},
{0, -1}
};
while (!pq.empty()) {
auto [d, x, y] = pq.top();
pq.pop();
if (d != dist[x][y]) continue;
for (auto [x1, y1] : dir) {
int nx = x + x1;
int ny = y + y1;
if (nx < 0 || nx >= r || ny < 0 || ny >= c) continue;
int w = grid[nx][ny] ? 0 : 1;
if (dist[nx][ny] > d + w) {
dist[nx][ny] = d + w;
pq.push({dist[nx][ny], nx, ny});
}
}
}
cout << dist[gx][gy];
}
