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// compile using g++ -O2 -o maze -Wall maze.cpp
// mazes _must_ have a border around them!

#include <cstdio>
#include <cstring>
#include <queue>

struct pos_t {
	int x;
	int y;
	int distance;
};

void printMap(int w, int h, int *map) {
	printf("Maze (%ix%i):\n", w, h);
	int x,y;
	for (x = 0; x < h; x++) {
		for (y = 0; y < w; y++) {
			int c = map[x * w + y];
			if (c < 0) {
				printf("%i", -c);
			} else {
				putc(c, stdout);
			}
		}
		putc('\n', stdout);
	}
}

void floydWarshall(int w, int h, int *map) {
	const int verticesCount = w*h;
	unsigned short paths[verticesCount][verticesCount];
	
	// fill the array, all edges are initially infinty
	memset(paths, 0xFF, sizeof(short) * verticesCount * verticesCount);
		
	int i,j,k;
	
	// set all i->i edges to cost 0
	// set all i->adjecent(i) to cost 1 or leave them at infinity if there's an obstacle
	for (i = 0; i < verticesCount; i++) {
		if (map[i] == '.') {
			paths[i][i] = 0;
			// left
			if (i > 0 && map[i-1] == '.')
				paths[i][i-1] = 1;
				
			// right
			if (i < verticesCount && map[i+1] == '.')
				paths[i][i+1] = 1;
				
			// top
			if (i > w && map[i-w] == '.')
				paths[i][i-w] = 1;
				
			// bottom
			if (i + w < verticesCount && map[i+w] == '.')
				paths[i][i+w] = 1;
		}
	}
	
	// the actual algorithm
	for (k = 0; k < verticesCount; k++) {
		for (i = 0; i < verticesCount; i++) {
			for (j = 0; j < verticesCount; j++) {
				if (paths[i][k] != 0xFFFF && paths[k][j] != 0xFFFF) {
					if (paths[i][k] + paths[k][j] < paths[i][j]) {
						paths[i][j] = paths[i][k] + paths[k][j];
					}
				}
			}
		}
	}
	
	puts("Fartest Distance is (Floyd Warshall):");
	// find greatest distance
	int distance = 0;
	int endi = 0;
	int endj = 0;
	for (i = 0; i < verticesCount; i++) {
		for (j = 0; j < verticesCount; j++) {
			if (paths[i][j] != 0xFFFF && paths[i][j] > distance) {
				distance = paths[i][j];
				endi = i;
				endj = j;
			}
		}
	}
	printf("(%i, %i) -> (%i, %i): %i\n", endi % w, endi / w, endj % w, endj / w, distance);
	map[endi] = 'S';
	map[endj] = 'E';
	printMap(w,h,map);
}

void hosamAly(int w, int h, int *map) {
	const size_t mapSize = w * h * sizeof(int);
	
	int x,y;
	pos_t fartestStart = {0,0,0};
	pos_t fartestEnd = {0,0,0};
		
	int *mapCopy = (int*)malloc(mapSize);
	std::queue<pos_t> myQueue;
	for (x = 1; x < w - 1; x++) { // we know there are borders, so just leave them out
		for (y = 1; y < h - 1; y++) {
			// flood fill the map and find the fartest point.
			memcpy(mapCopy, map, mapSize);
			pos_t startPos = {x, y, 0};
			myQueue.push(startPos);
			pos_t pos;
			while (!myQueue.empty()) {
				pos = myQueue.front();
				myQueue.pop();
				if (mapCopy[w * pos.y + pos.x] == '.') {
					mapCopy[w * pos.y + pos.x] = pos.distance;
				
					pos_t leftPos = {pos.x + 1, pos.y, pos.distance - 1};
					pos_t rightPos = {pos.x - 1, pos.y, pos.distance - 1};
					pos_t topPos = {pos.x, pos.y - 1, pos.distance - 1};
					pos_t bottomPos = {pos.x, pos.y + 1, pos.distance - 1};
					myQueue.push(leftPos);
					myQueue.push(rightPos);
					myQueue.push(topPos);
					myQueue.push(bottomPos);
					
					// is it farter than the old point?
					if (pos.distance < fartestEnd.distance) {
						fartestStart = startPos;
						fartestEnd = pos;
					}
				}
			}
		}
	}
	
	puts("Fartest Distance is (Hosam Aly):");
	printf("(%i, %i) -> (%i, %i): %i\n", fartestStart.x, fartestStart.y, fartestEnd.x, fartestEnd.y, -fartestEnd.distance);
	
	map[fartestStart.x + fartestStart.y * w] = 'S';
	map[fartestEnd.x + fartestEnd.y * w] = 'E';
	printMap(w,h,map);
	
	free(mapCopy);
}

int main(int argc, char *argv[]) {	
	int w,h;
	scanf("%i %i\n", &w, &h);
	
	int *map = (int*)malloc(w * h * sizeof(int));
	
	int x,y;
	// read maze
	for (y = 0; y < h; y++) {
		for (x = 0; x < w; x++) {
			map[y * w + x] = getc(stdin);
		}
		// get line break
		getc(stdin);
	}
		
	if (argc > 1 && (strcmp(argv[1], "-FW") == 0 || strcmp(argv[1], "-FloydWarshall") == 0)) {
		floydWarshall(w, h, map);
	} else if (argc > 1 && (strcmp(argv[1], "-HA") == 0 || strcmp(argv[1], "-HosamAly") == 0)) {
		hosamAly(w, h, map);
	} else {
		puts("No algorithm specified.");
	}
	
	free(map);
	
	return 0;
}