Python中使用实现输出哈沙德数的多种方法小结

def is_harshad_number(num):
    # 将数字转换为字符串以便处理各位数字
    num_str = str(num)
    
    # 计算各位数字之和
    digit_sum = 0
    for digit in num_str:
        digit_sum += int(digit)
    
    # 判断是否是哈沙德数
    return num % digit_sum == 0

# 测试示例
num1 = 18
num2 = 19

print(f"{num1} 是哈沙德数吗？ {is_harshad_number(num1)}")
print(f"{num2} 是哈沙德数吗？ {is_harshad_number(num2)}")

def digit_sum_recursive(num):
    if num == 0:
        return 0
    else:
        return num % 10 + digit_sum_recursive(num // 10)

def is_harshad_number_recursive(num):
    digit_sum = digit_sum_recursive(num)
    return num % digit_sum == 0

# 测试示例
num1 = 18
num2 = 19

print(f"{num1} 是哈沙德数吗？ {is_harshad_number_recursive(num1)}")
print(f"{num2} 是哈沙德数吗？ {is_harshad_number_recursive(num2)}")

def is_harshad_number_str(num):
    num_str = str(num)
    digit_sum = sum(int(digit) for digit in num_str)
    return num % digit_sum == 0

# 测试示例
num1 = 18
num2 = 19

print(f"{num1} 是哈沙德数吗？ {is_harshad_number_str(num1)}")
print(f"{num2} 是哈沙德数吗？ {is_harshad_number_str(num2)}")

def is_harshad_number_math(num):
    if num == 0:
        return False  # 0不是哈沙德数
        
    digit_sum = sum(int(digit) for digit in str(num))
    return num % digit_sum == 0

# 测试示例
num1 = 18
num2 = 19

print(f"{num1} 是哈沙德数吗？ {is_harshad_number_math(num1)}")
print(f"{num2} 是哈沙德数吗？ {is_harshad_number_math(num2)}")

def is_harshad_number_lambda(num):
    if num == 0:
        return False
    
    digit_sum = sum(map(int, str(num)))
    return num % digit_sum == 0

# 测试示例
num1 = 18
num2 = 19

print(f"{num1} 是哈沙德数吗？ {is_harshad_number_lambda(num1)}")
print(f"{num2} 是哈沙德数吗？ {is_harshad_number_lambda(num2)}")

from functools import reduce

def digit_sum_reduce(num):
    return reduce(lambda x, y: x + y, map(int, str(num)))

def is_harshad_number_reduce(num):
    if num == 0:
        return False
    
    digit_sum = digit_sum_reduce(num)
    return num % digit_sum == 0

# 测试示例
num1 = 18
num2 = 19

print(f"{num1} 是哈沙德数吗？ {is_harshad_number_reduce(num1)}")
print(f"{num2} 是哈沙德数吗？ {is_harshad_number_reduce(num2)}")