#include <algorithm>
#include <chrono>
#include <cmath>
#include <cstdlib>
#include <cstring>
#include <iostream>
#include <unistd.h>
#include <vector>
using namespace std;
using pi = pair<int, int>;
vector<int> *baseRows;
vector<int> *baseColumns;
int *reverseRows;
int *reverseColumns;
int *rowDepths;
int *columnDepths;
constexpr int NOT_FOUND = 10000;
template <bool Row>
char findPath(int **path, int depth, pi pos, pi target, int *min) {
path[pos.first][pos.second] = depth;
if (depth + 1 >= *min) return depth + 1 - *min;
if (depth > rowDepths[pos.second]) return true;
if (depth > columnDepths[pos.first]) return true;
rowDepths[pos.second] = depth + 1;
columnDepths[pos.first] = depth + 1;
int rev1 = reverseRows[pos.second];
int rev2 = reverseColumns[pos.first];
if (rev1) {
if (rev2) {
if (rev2 < rev1) {
*min = depth + rev2 - 1;
return rev2;
} else {
*min = depth + rev1 - 1;
return rev1;
}
}
else {
*min = depth + rev1 - 1;
return 1;
}
} else if (rev2) {
*min = depth + rev2 - 1;
return 1;
}
if constexpr (Row) {
for (int i : baseRows[pos.second]) {
int found = path[i][pos.second];
if (found <= depth + 1) continue;
char result = findPath<false>(path, depth + 1, { i, pos.second }, target, min);
if (result >= 1) return result - 1;
}
} else {
for (int i : baseColumns[pos.first]) {
int found = path[pos.first][i];
if (found <= depth + 1) continue;
char result = findPath<true>(path, depth + 1, { pos.first, i }, target, min);
if (result >= 1) return result - 1;
}
}
if constexpr (!Row) {
for (int i : baseRows[pos.second]) {
int found = path[i][pos.second];
if (found <= depth + 1) continue;
char result = findPath<false>(path, depth + 1, { i, pos.second }, target, min);
if (result >= 1) return result - 1;
}
} else {
for (int i : baseColumns[pos.first]) {
int found = path[pos.first][i];
if (found <= depth + 1) continue;
char result = findPath<true>(path, depth + 1, { pos.first, i }, target, min);
if (result >= 1) return result - 1;
}
}
return false;
}
void createReverse(pi pos, int depth, int max) {
if (reverseRows[pos.second] == 0 || depth < reverseRows[pos.second]) reverseRows[pos.second] = depth;
if (reverseColumns[pos.first] == 0 || depth < reverseColumns[pos.first]) reverseColumns[pos.first] = depth;
if (depth >= max) return;
for (int i : baseRows[pos.second]) {
createReverse({ i, pos.second }, depth + 1, max);
}
for (int i : baseColumns[pos.first]) {
createReverse({ pos.first, i }, depth + 1, max);
}
}
int main(int argc, char *argv[]) {
int height, width, count; cin >> height >> width >> count;
baseRows = new vector<int>[height];
baseColumns = new vector<int>[width];
for (int y = 0; y < height; y++) {
for (int x = 0; x < width; x++) {
char c; cin >> c;
if (c == '.') {
baseRows[y].push_back(x);
baseColumns[x].push_back(y);
}
}
}
// vector<pair<pi, pi>> queries;
// queries.reserve(count);
//
// for (int i = 0; i < count; i++) {
// int y1, x1, y2, x2; cin >> y1 >> x1 >> y2 >> x2;
//
// queries.push_back({ { x1 - 1, y1 - 1 }, { x2 - 1, y2 - 1 } });
// cout << y1 << endl;
// }
reverseRows = new int[height];
reverseColumns = new int[width];
rowDepths = new int[height];
columnDepths = new int[width];
int **path = new int*[width];
for (int i = 0; i < width; i++) {
path[i] = new int[height];
}
// auto startTime = chrono::high_resolution_clock::now();
for (int i = 0; i < count; i++) {
int y1, x1, y2, x2; cin >> y1 >> x1 >> y2 >> x2;
int min = NOT_FOUND;
pi start{ x1 - 1, y1 - 1}, end{ x2 - 1, y2 - 1 };
if (start.first == end.first && start.second == end.second) min = 0;
else {
for (int i = 0; i < width; i++)
memset((void*)(path[i]), 127, height * sizeof(int));
memset((void*)reverseRows, 0, height * sizeof(int));
memset((void*)reverseColumns, 0, width * sizeof(int));
memset((void*)rowDepths, 127, height * sizeof(int));
memset((void*)columnDepths, 127, width * sizeof(int));
createReverse(end, 1, 3);
for (int i = 0; i < height; i++)
sort(baseRows[i].begin(), baseRows[i].end(), [end](int p1, int p2) -> bool { return abs(p1 - end.first) < abs(p2 - end.first); });
for (int i = 0; i < width; i++)
sort(baseColumns[i].begin(), baseColumns[i].end(), [end](int p1, int p2) -> bool { return abs(p1 - end.second) < abs(p2 - end.second); });
findPath<true>(path, 1, start, end, &min);
// findPath<false>(path, 1, start, end, &min);
if (min == NOT_FOUND) min = -1;
}
cout << min << '\n';
}
// auto endTime = chrono::high_resolution_clock::now();
// cout << endTime - startTime << endl;