Import provided c starting file

main.cc

@@ -0,0 +1,149 @@
+// Example of world building, display, and successor computation for the artificial 
+// intelligence path-finding lab
+//
+// Author: Didier Lime
+// Date: 2018-10-03
+
+#include <iostream>
+#include <list>
+#include <cstdlib>
+#include <ctime>
+
+using namespace std;
+
+class World
+{
+    private:
+        // Number of columns
+        unsigned int L;
+        
+        // Number of lines
+        unsigned int H;
+
+        // Unidimensional array for tiles
+        int* w;
+    
+    public:
+        // Constructor
+        World(unsigned int L, unsigned int H, double P)
+        {
+            this->L = L;
+            this->H = H;
+            this->w = new int[L*H]();
+
+            // Add walls to the first and last columns
+            for (unsigned int i = 0; i < H; i++)
+            {
+                this->w[i * L] = 1;
+                this->w[i * L + L - 1] = 1;
+            }
+
+            // Add walls to the first and last lines
+            for (unsigned int j = 0; j < L; j++)
+            {
+                this->w[j] = 1;
+                this->w[(H - 1) * L + j] = 1;
+            }
+
+            for (unsigned int i = 0; i < H; i++)
+            {
+                for (unsigned int j = 0; j < L; j++)
+                {
+                    // add a wall in this tile with probability P and provided that it is neither
+                    // the starting tile nor the goal tile 
+                    if ((double) rand() / RAND_MAX < P && !(i == 1 && j == 1) && !(i == H - 2 && j == L - 2))
+                    {
+                        this->w[i * L + j] = 1;
+                    }
+                }
+            }
+        }
+
+        // Display the world
+        void display()
+        {
+            for (unsigned int i = 0; i < H; i++)
+            {
+                for (unsigned int j = 0; j < L; j++)
+                {
+                    switch (this->w[i * L + j])
+                    {
+                        case 0:
+                            cout << ".";
+                            break;
+
+                        case 1:
+                            cout << "W";
+                            break;
+                    }
+                }
+                cout << endl;
+            }
+        }
+
+        // compute the successors of tile number i in world w
+        // we return the number n of valid successors
+        // the actual list is in array r where only the first n
+        // elements are significant
+        unsigned int successors(unsigned int i, unsigned int r[4])
+        {
+            unsigned int n = 0;
+
+            if (i >= 0 && i < this->L * this->H && this->w[i] != 1)
+            {
+                // if i is a correct tile number (inside the array and not on a wall)
+                // look in the four adjacent tiles and keep only those with no wall
+                const unsigned int moves[] = { i - 1, i + 1, i - L, i + L};
+                
+                for (unsigned int k = 0; k < 4; k++)
+                {
+                    if (this->w[moves[k]] != 1)
+                    {
+                        r[n] = moves[k];
+                        n++;
+                    }
+                }
+            }
+
+            return n;
+        }
+
+        // Depth-first search
+        // starting from tile number s0, find a path to tile number t
+        // return true if such a path exists, false otherwise
+        // if it exists the path is given in variable path (hence the reference &)
+        bool dfs(unsigned int s0, unsigned int t, list<unsigned int>& path)
+        {
+            bool r = false;
+
+            // ... Complete here ...
+
+            return r;
+        } 
+};
+
+int main()
+{
+    // Initialise the random number generator
+    srand(time(0));
+
+    // Create a world
+    World w(20, 10, 0.2);
+
+    // Display it
+    w.display();
+
+    // Print the tile numbers of the successors of the starting tile (1, 1)
+    unsigned int succs[4];
+    unsigned int n = w.successors(21, succs);
+
+    for (unsigned int k = 0; k < n; k++)
+    {
+        cout << succs[k] << " ";
+    }
+    cout << endl;
+
+    return 0;
+}
+
+