s = "Hello"
for char in s:
    print(f"'{char}' 的ASCII码: {ord(char)}")
print(f"ASCII码65对应的字符: {chr(65)}")
import math

# 定义向量
A = [3, 4]
B = [1, 2]

# 1. 计算 A + B（对应元素相加）
A_plus_B = [A[0] + B[0], A[1] + B[1]]
print("=== 题目3 计算结果 ===")
print(f"1. A + B = {A_plus_B}")

# 2. 计算 2 × A（数乘向量，每个元素乘系数）
two_times_A = [2 * A[0], 2 * A[1]]
print(f"2. 2 × A = {two_times_A}")

# 3. 计算 A 的长度（模），公式：||A|| = √(x² + y²)
A_norm = math.sqrt(A[0] ** 2 + A[1] ** 2)
print(f"3. A 的长度（模） = {A_norm}")
import math

# 定义向量
A = [3, 4]
B = [1, 2]

# 1. 计算 A + B（对应元素相加）
A_plus_B = [A[0] + B[0], A[1] + B[1]]
print("=== 题目3 计算结果 ===")
print(f"1. A + B = {A_plus_B}")

# 2. 计算 2 × A（数乘向量，每个元素乘系数）
two_times_A = [2 * A[0], 2 * A[1]]
print(f"2. 2 × A = {two_times_A}")

# 3. 计算 A 的长度（模），公式：||A|| = √(x² + y²)
A_norm = math.sqrt(A[0] ** 2 + A[1] ** 2)
print(f"3. A 的长度（模） = {A_norm}")
# 题目1
print("=== 题目1 ===")
s = "Hello"
for char in s:
    print(f"'{char}' 的ASCII码: {ord(char)}")
print(f"ASCII码65对应的字符: {chr(65)}")

# 题目3
print("\n=== 题目3 ===")
A = [3, 4]
B = [1, 2]
# 1. A+B
A_plus_B = [A[0]+B[0], A[1]+B[1]]
print(f"A + B = {A_plus_B}")
# 2. 2*A
two_A = [2*A[0], 2*A[1]]
print(f"2 * A = {two_A}")
# 3. A的模
import math
A_norm = math.sqrt(A[0]**2 + A[1]**2)
print(f"A的长度(模) = {A_norm}")

# 题目4
print("\n=== 题目4 ===")
A = [1, 2, 3]
B = [4, 5, 6]
# 1. 点积
dot_product = sum(a*b for a,b in zip(A,B))
print(f"A·B = {dot_product}")
# 2. 余弦相似度
A_norm = math.sqrt(sum(a**2 for a in A))
B_norm = math.sqrt(sum(b**2 for b in B))
cos_sim = dot_product / (A_norm * B_norm)
print(f"余弦相似度 = {cos_sim:.4f}")
# 3. A=[0,1], B=[0,1]的余弦相似度
A2 = [0, 1]
B2 = [0, 1]
dot_product2 = sum(a*b for a,b in zip(A2,B2))
A2_norm = math.sqrt(sum(a**2 for a in A2))
B2_norm = math.sqrt(sum(b**2 for b in B2))
cos_sim2 = dot_product2 / (A2_norm * B2_norm)
print(f"A=[0,1], B=[0,1]的余弦相似度 = {cos_sim2}")