import math
import matplotlib.pyplot as plt

def fx(x):
    return math.exp(x)-math.sin(x)

def huatu(a, b, buchang):
    x = [a + (b-a)*i*buchang for i in range(int(1/buchang+1))]
    y = [fx(i) for i in x]
    plt.plot(x, y)
    plt.axhline(0, color='black', lw=1)
    for i in range(len(x)-1):
        if y[i] * y[i+1] < 0:
            print(f"({x[i]},{y[i]}),({x[i+1]},{y[i+1]})")
    plt.xlabel("x")
    plt.ylabel("f(x)")
    plt.show()
    return x, y


if __name__ == "__main__":
    a = -2*math.pi
    b = math.pi
    huatu(a, b, 0.00001)