import matplotlib.pyplot as plt

def main():
    chemin = [(0, 0), (1, 0), (1, 1), (1, 2), (0, 2), (0, 3), (1, 3), (2, 3), (3, 3)]
    vx = []
    vy = []
    for (y,x) in chemin: 
        vx.append(x+1)
        vy.append(4-y)
    
    
    plt.ylabel("y")
    plt.xlabel("x")
    plt.plot(vx, vy)
    plt.scatter(vx, vy, color='red',s=60)
    
    
    plt.show()

if __name__ == "__main__":
    main()