Lintcode54 String to Integer II solution 题解

【题目描述】

Implement function atoi to convert a string to an integer.If no valid conversion could be performed, a zero value is returned.If the correct value is out of the range of representable values, INT_MAX (2147483647) or INT_MIN (-2147483648) is returned.

实现atoi这个函数，将一个字符串转换为整数。如果没有合法的整数，返回0。如果整数超出了32位整数的范围，返回INT_MAX(2147483647)如果是正整数，或者INT_MIN(-2147483648)如果是负整数。

【题目链接】

www.lintcode.com/en/problem/string-to-integer-ii/

【题目解析】

经典的字符串转整数题，边界条件比较多，比如是否需要考虑小数点，空白及非法字符的处理，正负号的处理，科学计数法等。最先处理的是空白字符，然后是正负号，接下来只要出现非法字符(包含正负号，小数点等，无需对这两类单独处理)即退出，否则按照正负号的整数进位加法处理。

【参考答案】

www.jiuzhang.com/solutions/string-to-integer-ii/

时间： 2024-08-01 21:58:25

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