import matplotlib.pyplot as plt

backends = ['ibm', 'russian']
mean_rewards = [0.842, 0.791]
std_rewards = [0.034, 0.052]

plt.bar(backends, mean_rewards, yerr=std_rewards, capsize=10, color=['blue', 'red'])
plt.title("Backend Performance Comparison")
plt.ylabel("Mean Reward ± Std Dev")
plt.show()