【Python】字符串的 “*” “+”
1:在数学运算里,“*”,就是两个数字相乘,例如:
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>>> 9 * 9 81 >>> |
2:字符串中也可以使用“*”,相当于复制字符串,例如:
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>>> 'Abc' * 3 'AbcAbcAbc' >>> ## 当数字小于等于0时,返回的结果为‘’ >>> 'Abc' * 0 '' >>> 'Abc' * -5 '' >>> ## 字符串只能与整数相乘,如果是浮点数,则会报错 >>> 'Abc' * 9.5 Traceback (most recent call last): File "<stdin>", line 1, in <module> TypeError: can't multiply sequence by non-int of type 'float' >>> |
3:字符串相加,这没什么好说的
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>>> 'Hello' + 'World' 'HelloWorld' >>> |
4:列表相加、相乘
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>>> ['Hello'] + ['World'] ['Hello', 'World'] >>> >>> ['Hello','World'] * 3 ['Hello', 'World', 'Hello', 'World', 'Hello', 'World'] >>> |
3:元组相加、相乘
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>>> (1,2,3) * 2 (1, 2, 3, 1, 2, 3) >>> >>> (1,2,3) + (4,5,6) (1, 2, 3, 4, 5, 6) >>> >>> ('a','b','c') * 3 ('a', 'b', 'c', 'a', 'b', 'c', 'a', 'b', 'c') >>> >>> ('a','b','c') + ('d','e') ('a', 'b', 'c', 'd', 'e') >>> |