标签：style blog color io os ar strong for div
Implement atoi to convert a string to an integer.
Hint: Carefully consider all possible input cases. If you want a challenge, please do not see below and ask yourself what are the possible input cases.
Notes: It is intended for this problem to be specified vaguely (ie, no given input specs). You are responsible to gather all the input requirements up front.
思路：
1 class Solution { 2 public: 3 int atoi( const char *str ) { 4 double ret = 0, sign = 1.0; 5 while( *str != ‘\0‘ && *str == ‘ ‘ ) { ++str; } 6 if( *str == ‘+‘ || *str == ‘-‘ ) { sign = *(str++) == ‘+‘ ? 1.0 : -1.0; } 7 while( *str >= ‘0‘ && *str <= ‘9‘ ) { 8 ret = 10*ret + sign*( *(str++)-‘0‘ ); 9 } 10 if( ret > INT_MAX ) { return INT_MAX; } 11 if( ret < INT_MIN ) { return INT_MIN; } 12 return (int)ret; 13 } 14 };
标签：style blog color io os ar strong for div
原文地址：http://www.cnblogs.com/moderate-fish/p/3960698.html
