cod_1_and_2

Example Python program cod_1_and_2.py Python version 3.x or newer. To check the Python version use:

python --version

Methods

• def dfs(start, visited=[]):
• def bfs(start, end):

Code

Python example

 # cod 1:

# https://docs.python.org/2/tutorial/datastructures.html#dictionaries
grap = {0: [1], 1: [0, 2], 2: [1], 3: [1, 4], 4: [3]}


# https://docs.python.org/2/tutorial/controlflow.html#defining-functions
def dfs(start, visited=[]):
    # https://docs.python.org/2/tutorial/introduction.html#lists
    visited.append(start)

    # https://docs.python.org/2/tutorial/controlflow.html#for-statements
    for i in grap.get(start):

        # https://docs.python.org/2/tutorial/controlflow.html#if-statements
        if i not in visited:
            dfs(i, visited)
    return visited

# https://docs.python.org/3.3/library/functions.html?highlight=print#print
print(dfs(4))

# cod 2:

# https://docs.python.org/2/tutorial/datastructures.html#dictionaries
graph = {0:[1], 1:[0,2], 2:[1], 3:[1,4], 4:[3]}

# https://docs.python.org/2/tutorial/controlflow.html#defining-functions
def bfs(start, end):
    # https://docs.python.org/2/tutorial/introduction.html#lists
    queue = [[start]]
    # https://docs.python.org/2/tutorial/datastructures.html#sets
    visited = set()

    # https://docs.python.org/2/tutorial/controlflow.html#break-and-continue-statements-and-else-clauses-on-loops
    while queue:
        # https://docs.python.org/3.3/tutorial/datastructures.html#using-lists-as-queues
        path = queue.pop(0)

        v = path[-1]

        # https://docs.python.org/2/tutorial/controlflow.html#if-statements
        if v == end:
            return path
        elif v not in visited:
            for vizinho in graph.get(v):
                # https://docs.python.org/2/tutorial/introduction.html#lists
                new_path = list(path)
                new_path.append(vizinho)
                queue.append(new_path)
                print(queue)
            visited.add(v)

# https://docs.python.org/3.3/library/functions.html?highlight=print#print
print(bfs(1,4))

Useful Links

• Articles: https://python-commandments.org/
• Python shell: https://bsdnerds.org/learn-python/
• Tutorial: https://pythonprogramminglanguage.com/