leetcode String to Integer (atoi)
来源:互联网 发布:男生喜欢手办恶心知乎 编辑:程序博客网 时间:2024/05/11 18:37
The function first discards as many whitespace characters as necessary until the first non-whitespace character is found. Then, starting from this character, takes an optional initial plus or minus sign followed by as many numerical digits as possible, and interprets them as a numerical value.
The string can contain additional characters after those that form the integral number, which are ignored and have no effect on the behavior of this function.
If the first sequence of non-whitespace characters in str is not a valid integral number, or if no such sequence exists because either str is empty or it contains only whitespace characters, no conversion is performed.
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.
class Solution { public: int atoi(const char *str) { bool sign = true, signExist = false, digitExist = false, spaceExist = false; long long res = 0; while (*str == ' ') ++str; while (*str) { if (*str == '-' || *str == '+') { if (signExist || digitExist || spaceExist) break; signExist = true; sign = *str == '-' ? false : true; } else if (*str >= '0' && *str <= '9'){ if (spaceExist) break; digitExist = true; res *= 10; res += *str - '0'; if (sign && res > INT_MAX) return INT_MAX; else if (!sign && 0-res < INT_MIN) return INT_MIN; } else if (*str == ' ') spaceExist = true; else break; ++str; } return sign ? (int)res : (int)(0 - res); }};
- LeetCode:String to Integer (atoi)
- LeetCode: String to Integer (atoi)
- LeetCode String to Integer(atoi)
- LeetCode :String to Integer (atoi)
- Leetcode: String to Integer (atoi)
- Leetcode : String to Integer (atoi)
- 【leetcode】String to Integer (atoi)
- [LeetCode]String to Integer (atoi)
- LeetCode-String to Integer (atoi)
- [leetcode] String to Integer (atoi)
- LeetCode - String to Integer (atoi)
- 【leetcode】String to Integer (atoi)
- LeetCode - String to Integer (atoi)
- LeetCode: String to Integer (atoi)
- Leetcode: String to Integer (atoi)
- [LeetCode] String to Integer (atoi)
- leetcode String to Integer (atoi)
- [LeetCode]String to Integer (atoi)
- spring mvc:处理表单上的多选框
- UML实践----用例图、顺序图、状态图、类图、包图、协作图
- 从海康7816的ps流里获取数据h264数据
- Dom4j 使用简介
- v8学习---使用内部字段给js添加全局变量
- leetcode String to Integer (atoi)
- YoukuFetcher
- MySQL忘记密码和重置密码的解决方法总结
- qt 5.1.1静态编译
- 熵推导
- 俞敏洪:像水一样积蓄自己的力量
- android4目录结构
- 学习笔记和商业笔记的差异
- linux 下各个头文件的作用(linux 2.6内核 s3c24xx)