print(" 题目1")
s = "Hello"
for c in s:
    print(f"'{c}' 的ASCII码: {ord(c)}")
print(f"ASCII码65对应的字符: {chr(65)}")
import math
print("题目3 ")
A = [3, 4]
B = [1, 2]
A_plus_B = [A[0] + B[0], A[1] + B[1]]
print("A + B =", A_plus_B)
two_times_A = [2 * A[0], 2 * A[1]]
print("2 × A =", two_times_A)
A_norm = math.sqrt(A[0] ** 2 + A[1] ** 2)
print("A 的模 =", A_norm)
print(" 题目4 ")
A = [1, 2, 3]
B = [4, 5, 6]
dot_product = sum(a * b for a, b in zip(A, B))
print("A·B =", dot_product)
def vector_norm(v):
    return math.sqrt(sum(x ** 2 for x in v))
norm_A = vector_norm(A)
norm_B = vector_norm(B)
cos_sim = dot_product / (norm_A * norm_B)
print("余弦相似度 =", cos_sim)
A_new = [1, 0]
B_new = [0, 1]
dot_product_new = sum(a * b for a, b in zip(A_new, B_new))
norm_A_new = vector_norm(A_new)
norm_B_new = vector_norm(B_new)
cos_sim_new = dot_product_new / (norm_A_new * norm_B_new)
print("A=[1,0], B=[0,1] 的余弦相似度 =", cos_sim_new)
print("原因：两个向量正交,点积为0,因此余弦相似度为0")