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#include <cstring>
#include <iostream>
#include <stack>
using namespace std;
#define N 4
#define M 5
class node {
public:
int x, y;
int dir;
node(int i, int j)
{
x = i;
y = j;
// Initially direction
// set to 0
dir = 0;
}
};
// maze of n*m matrix
int n = N, m = M;
// Coordinates of food
int fx, fy;
bool visited[N][M];
bool isReachable(int maze[N][M])
{
// Initially starting at (0, 0).
int i = 0, j = 0;
cout << '[' << i << ':' << j << ']';
stack<node> s;
node temp(i, j);
s.push(temp);
while (!s.empty()) {
// Pop the top node and move to the
// left, right, top, down or retract
// back according the value of node's
// dir variable.
temp = s.top();
int d = temp.dir;
i = temp.x, j = temp.y;
// Increment the direction and
// push the node in the stack again.
temp.dir++;
s.pop();
s.push(temp);
// If we reach the Food coordinates
// return true
if (i == fx and j == fy) {
return true;
}
// Checking the Up direction.
if (d == 0) {
if (i - 1 >= 0 and maze[i - 1][j] == 1 and
!visited[i - 1][j]) {
cout <<'['<< i - 1 << ':'<<j << ']' ;
node temp1(i - 1, j);
visited[i - 1][j] = true;
s.push(temp1);
}
}
// Checking the left direction
else if (d == 1) {
if (j - 1 >= 0 and maze[i][j - 1] == 1 and
!visited[i][j - 1]) {
cout << '[' << i << ':' << j-1 << ']' ;
node temp1(i, j - 1);
visited[i][j - 1] = true;
s.push(temp1);
}
}
// Checking the down direction
else if (d == 2) {
if (i + 1 < n and maze[i + 1][j] == 1 and
!visited[i + 1][j]) {
cout << '[' << i + 1 << ':' << j << ']' ;
node temp1(i + 1, j);
visited[i + 1][j] = true;
s.push(temp1);
}
}
// Checking the right direction
else if (d == 3) {
if (j + 1 < m and maze[i][j + 1] == 1 and
!visited[i][j + 1]) {
cout << '[' << i << ':' << j + 1<< ']' ;
node temp1(i, j + 1);
visited[i][j + 1] = true;
s.push(temp1);
}
}
// If none of the direction can take
// the rat to the Food, retract back
// to the path where the rat came from.
else {
visited[temp.x][temp.y] = false;
s.pop();
}
//system("pause");
}
// If the stack is empty and
// no path is found return false.
return false;
}
// Driver code
int main()
{
// Initially setting the visited
// array to true (unvisited)
memset(visited, false, sizeof(visited));
// Maze matrix
int maze[N][M] = {
{ 1, 0, 1, 1, 0 },
{ 1, 1, 1, 0, 1 },
{ 0, 1, 0, 1, 1 },
{ 1, 1, 1, 1, 1 }
};
// Food coordinates
fx = 2;
fy = 3;
if (isReachable(maze)) {
cout << "Path Found!" << '\n';
}
else
cout << "No Path Found!" << '\n';
return 0;
}
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