FindMinCostPath algorithm Added

Author: suren-rjs

findShortestPathInMaze/src/FindLowCostPath.java

@@ -0,0 +1,65 @@
+import java.util.Comparator;
+import java.util.PriorityQueue;
+
+class FindLowCostPath {
+
+ public static void main(String[] args) {
+ int[][] maze = {
+ {31, 100, 65, 12, 18},
+ {10, 13, 47, 157, 6},
+ {100, 113, 174, 11, 33},
+ {88, 124, 41, 20, 140},
+ {99, 32, 111, 41, 20}
+ };
+
+ findShortCostPath(maze);
+ }
+
+ private static void findShortCostPath(int[][] maze) {
+ int X = maze.length, Y = maze[0].length;
+ int[] mx = {-1, 0, 1, 0}, my = {0, 1, 0, -1};
+ int[][] costPathArray = new int[X][Y];
+ for (int i = 0; i < X; i++) {
+ for (int j = 0; j < Y; j++) {
+ costPathArray[i][j] = Integer.MAX_VALUE;
+ }
+ }
+
+ costPathArray[0][0] = maze[0][0];
+ PriorityQueue<Cell> pq = new PriorityQueue<>(X * Y, Comparator.comparing(a -> a.distance));
+
+ Cell tempCell;
+ pq.add(new Cell(0, 0, maze[0][0]));
+
+ while ((tempCell = pq.poll()) != null) {
+ for (int i = 0; i < 4; i++) {
+ int tempXMove = tempCell.x + mx[i];
+ int tempYMove = tempCell.y + my[i];
+ if (tempXMove > -1 && tempYMove > -1 && tempXMove < X && tempYMove < Y) {
+ int tempMovedValue = maze[tempXMove][tempYMove];
+ int updatedCurrentCell = costPathArray[tempCell.x][tempCell.y];
+ int existCostCellValue = costPathArray[tempXMove][tempYMove];
+ if (existCostCellValue > tempMovedValue + updatedCurrentCell) {
+ if (costPathArray[tempXMove][tempYMove] != Integer.MAX_VALUE) {
+ Cell existCell = new Cell(tempXMove, tempYMove, costPathArray[tempXMove][tempYMove]);
+ pq.remove(existCell);
+ }
+ costPathArray[tempXMove][tempYMove] = tempMovedValue + updatedCurrentCell;
+ pq.add(new Cell(tempXMove, tempYMove, costPathArray[tempXMove][tempYMove]));
+ }
+ }
+ }
+ }
+ System.out.println(costPathArray[X - 1][Y - 1]);
+ }
+
+ static class Cell {
+ int x, y, distance;
+
+ public Cell(int x, int y, int distance) {
+ this.x = x;
+ this.y = y;
+ this.distance = distance;
+ }
+ }
+}