Write a program that solves 15-puzzle problems using heuristic functions and a best-first or A* search. You can also add pruning, backward, bidirectional, or staged search modifications. But no problem decomposition strategies! Use whatever language/machine you want. Input: Initial state only (The Goal state is fixed at ON 1 3 4 5 7 8 9 10 11 12 13 14 15 (1) Output: 1. Number of nodes generated (open + closed sets) 2. Length of the solution path 3. Solution path from IS to us using Right, Left, Up, and Down operators (= how you move the "blank") with resulting board configurations. Hand in: 1. Documented program 2. A detailed, specific description of the heuristic function(s) used 3. A description of other modifications to search used (if any) 4. 3 executions of your program on the following data: Data: 1. 1 2 0 3 6 7 11 5 9 12 13 10 14 15 2. 1 2 3 12 13 14 11 [] 15 10 9 8 4 5 6 7 (spiral) 3. ( 15 14 13 12 11 10 9 8 7 6 5 4 3 2 1 (backward) Write a program that solves 15-puzzle problems using heuristic functions and a best-first or A* search. You can also add pruning, backward, bidirectional, or staged search modifications. But no problem decomposition strategies! Use whatever language/machine you want. Input: Initial state only (The Goal state is fixed at ON 1 3 4 5 7 8 9 10 11 12 13 14 15 (1) Output: 1. Number of nodes generated (open + closed sets) 2. Length of the solution path 3. Solution path from IS to us using Right, Left, Up, and Down operators (= how you move the "blank") with resulting board configurations. Hand in: 1. Documented program 2. A detailed, specific description of the heuristic function(s) used 3. A description of other modifications to search used (if any) 4. 3 executions of your program on the following data: Data: 1. 1 2 0 3 6 7 11 5 9 12 13 10 14 15 2. 1 2 3 12 13 14 11 [] 15 10 9 8 4 5 6 7 (spiral) 3. ( 15 14 13 12 11 10 9 8 7 6 5 4 3 2 1 (backward)