Your task is to write a function, depthFirstSearch, that performs a depth first search on a graph starting at the given vertex. It should print out the vertices as they are visited. If a vertex has multiple neighbours, visit the neighbour with the smallest vertex number first.
Hint: You are not provided with a stack ADT, so you must use recursion.
Click here to download a zip of the files.
| Graph.c | Contains the implementation of a graph ADT |
| Graph.h | Contains the interface of the graph ADT |
| testDepthFirstSearch.c | Contains the main function, which reads in a graph and a starting vertex from standard input, and then calls depthFirstSearch. |
| depthFirstSearch.c | Contains depthFirstSearch, the function you must implement |
| Makefile | A makefile to compile your code |
| tests/ | A directory containing the inputs and expected outputs for some basic tests |
| autotest | A script that uses the tests in the tests directory to autotest your solution. You should only run this after you have tested your solution manually. |
Your program should behave like these examples:
$ ./testDepthFirstSearch
Enter number of vertices: 9
Enter number of edges: 9
Enter edges in the form v-w: 0-1 0-7 1-2 1-5 3-4 3-5 3-6 3-7 5-8
Graph: nV = 9
Edges:
0: 0-1 0-7
1: 1-0 1-2 1-5
2: 2-1
3: 3-4 3-5 3-6 3-7
4: 4-3
5: 5-1 5-3 5-8
6: 6-3
7: 7-0 7-3
8: 8-5
Enter src: 0
Depth first search starting at vertex 0: 0 1 2 5 3 4 6 7 8
$ ./testDepthFirstSearch
Enter number of vertices: 8
Enter number of edges: 8
Enter edges in the form v-w: 0-1 1-2 2-3 3-4 4-5 5-6 6-7 7-0
Graph: nV = 8
Edges:
0: 0-1 0-7
1: 1-0 1-2
2: 2-1 2-3
3: 3-2 3-4
4: 4-3 4-5
5: 5-4 5-6
6: 6-5 6-7
7: 7-0 7-6
Enter src: 3
Depth first search starting at vertex 3: 3 2 1 0 7 6 5 4
$ ./testDepthFirstSearch
Enter number of vertices: 10
Enter number of edges: 9
Enter edges in the form v-w: 0-1 1-2 1-3 2-4 2-5 3-5 3-6 7-8 8-9
Graph: nV = 10
Edges:
0: 0-1
1: 1-0 1-2 1-3
2: 2-1 2-4 2-5
3: 3-1 3-5 3-6
4: 4-2
5: 5-2 5-3
6: 6-3
7: 7-8
8: 8-7 8-9
9: 9-8
Enter src: 6
Depth first search starting at vertex 6: 6 3 1 0 2 4 5
You can test your program manually by compiling your code using make, and then running ./testDepthFirstSearch, as shown above. After you are satisfied with your solution, you can autotest it by running ./autotest. This will run some basic tests on your program.