错误的代码：

class Solution {public:    bool isNumeric(char* string)    {        if(string == NULL)            return false;        if(*string == '+' || *string == '-')            string++;        if(*string == '\0')            return false;        bool flag = true;        ScanDigit(string);        if(*string != '\0'){            if(*string == '.'){                string++;                ScanDigit(string);                if(*string == 'e' || *string == 'E')                    flag = Exponential(string+1);            }            else if(*string == 'e' || *string == 'E')                flag = Exponential(string+1);            else                flag = false;        }        return flag && (*string == '\0');    }    void ScanDigit(char *string){        while(*string >= '0' && *string <= '9' && *string != '\0')            string++;    }    bool Exponential(char *string){        if(*string == '+' || *string == '-')            string++;        if(*string == '\0')            return false;        ScanDigit(string);        if(*string == '\0')            return true;        else            return false;    }};