RatInAMaze added in Backtracking

Author: chiranjeev-thapliyal

Backtracking/RatInAMaze.js

@@ -0,0 +1,55 @@
+/*
+ * Problem Statement:
+ * - Given a NxN grid, find whether rat in cell (0,0) can reach target(N-1,N-1);
+ * - In grid "0" represent blocked cell and "1" represent empty cell
+ *
+ */
+
+const outOfBoundary = (grid, currentRow, currentColumn) => {
+  if (currentRow < 0 || currentColumn < 0 || currentRow >= grid.length || currentColumn >= grid[0].length) return true
+  else return false
+}
+
+const isPossible = (grid, currentRow, currentColumn) => {
+  if (outOfBoundary(grid, currentRow, currentColumn)) return false
+
+  console.log(currentRow, currentColumn)
+  if (grid[currentRow][currentColumn] === 0) return false
+
+  if (currentRow === targetRow && currentColumn === targetColumn) {
+    return true
+  }
+
+  const directions = [
+    [1, 0],
+    [0, 1],
+    [-1, 0],
+    [0, -1]
+  ]
+
+  for (let i = 0; i < directions.length; i++) {
+    const nextRow = currentRow + directions[i][0]; const nextColumn = currentColumn + directions[i][1]
+    grid[currentRow][currentColumn] = 0
+    if (isPossible(grid, nextRow, nextColumn)) return true
+    grid[currentRow][currentColumn] = 1
+  }
+  return false
+}
+
+// Driver Code
+
+const grid = [
+  [1, 1, 1, 1],
+  [1, 0, 0, 1],
+  [0, 1, 0, 1],
+  [1, 1, 1, 1]
+]
+
+const targetRow = grid.length - 1
+const targetColumn = grid[0].length - 1
+
+if (isPossible(grid, 0, 0)) {
+  console.log('Possible')
+} else {
+  console.log('Not Possible')
+}