50 lines
1.2 KiB
Python
50 lines
1.2 KiB
Python
# 1. 计算数列的和
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numbers = [2, 4, 6, 8, 10]
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total = 0
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for num in numbers:
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total += num
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print(f"数列的和是 {total}")
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# 2. 统计字符串中字符出现的次数
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s = input("请输入字符串：")
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char_count = {}
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for char in s:
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char_count[char] = char_count.get(char, 0) + 1
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for char, count in char_count.items():
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print(f"{char}: {count}")
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# 3. 找出列表中的所有偶数
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lst = [1, 2, 3, 4, 5, 6, 7, 8, 9, 10]
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even_numbers = []
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for num in lst:
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if num % 2 == 0:
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even_numbers.append(num)
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print("偶数有：", *even_numbers)
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# 4.计算列表中所有数字的平方
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lst = [1, 2, 3, 4, 5]
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squared_list = []
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for num in lst:
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squared_list.append(num ** 2)
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print(f"平方后的列表是：{squared_list}")
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# 5.计算字符串的反向
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s = input("请输入一个字符串：")
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reversed_str = ""
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for char in s:
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reversed_str = char + reversed_str
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print(f"反转后的字符串是：{reversed_str}")
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# 6.找出数组中的重复元素
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arr = [1, 2, 3, 4, 2, 5, 3]
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duplicates = []
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for i in range(len(arr)):
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if arr[i] in arr[:i] and arr[i] not in duplicates:
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duplicates.append(arr[i])
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print("重复的元素有：", *duplicates)
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