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LeetCode 8 :String to Integer (atoi)

问题是这样子的:

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.

平时写程序过于急躁,思考不深入,写这个看似容易的程序真是死了一大批脑细胞啊!!!反思,对于数值处理的问题,以及字符串处理的问题。

最重要的是:会不会溢出,会不会越界!!!

以下是我的代码,感觉略臭略长。如有大神帮改,感激不尽啊!!!

class Solution{public:    int atoi(const char *str)    {        int ret = 0;        const char *fStr = str;        int signflag = 1;        int signCount = 0;        int intCount = 0;        if(fStr == NULL )        {            return 0;        }        while(*fStr != \0)        {            if(*fStr == 0x2D)            {                signflag = -1;                ++signCount;                fStr++;            }            if(*fStr == 0x2B)            {                signflag = 1;                ++signCount;                fStr++;            }            if(signCount > 1)            {                return 0;            }            if(isdigit(*fStr))            {                if(ret == INT_MAX/10 && *fStr >= 0x38 && signflag == 1)                {                    return INT_MAX;                }                else if(ret == INT_MAX/10 && *fStr > 0x38 && signflag == -1)                {                    return INT_MIN;                }                ret = 10 *ret + (*fStr-0x30);                ++fStr;                ++intCount;                if(intCount > 10)                {                    return signflag >0 ? -INT_MIN-1 : INT_MIN;                }            }            else if(*fStr == )            {                if(intCount >= 1)                {                    return ret * signflag;                }                else if(signCount >= 1 && intCount ==0 )                {                    return 0;                }                fStr++;            }            else                 return ret * signflag;        }        return ret * signflag;    }};

任重道远,爱情不光是甜蜜,更是一份责任。。。加油!!!

LeetCode 8 :String to Integer (atoi)