def get_env_feedback(S, A):
    # This is how agent will interact with the environment
    if A == 'right':    
        S_ = S + 1
    else:   # move left
        S_ = S - 1
    if S_ == -1:   
        S_ = 0
    if S_ == N_STATES - 1:   
        S_ = 'terminal'
        R = 1
    else: R = 0
    return S_, R

def get_env_feedback(S, A):
    # This is how agent will interact with the environment
    if A == 'right':    
        if S == N_STATES - 2:   
            S_ = 'terminal'
            R = 1
        else:
            S_ = S + 1
            R = 0
    else:   # move left
        R = 0
        if S == 0:
            S_ = S  
        else:
            S_ = S - 1
    return S_, R