leetcode valid number

细节很多，不是很容易做对

class Solution {
public:
    bool isNumber(const char *s) 
    {
        bool flag;
        while(*s==' ')
        s++;
        const char *s2=s+strlen(s)-1;
        while(*s2==' ')
        {
            s2--;
        }
        if(*s=='+'||*s=='-')s++; 
        const char *s1=s;
        int point=0;
        int e=0;
        int count=0;
        while(*s1!='\0'&&s1<=s2)
        {
          if(isdigit(*s1)){s1++;count++;}
          else if(*s1=='.'&&e==0){s1++;point++;}
          else if(*s1=='e'&&s1!=s&&count>=1)
          {
              if(isdigit(*(s1+1)))
              {s1=s1+2;e++;}
              else if((s1+2<=s2)&&(*(s1+1)=='+'||*(s1+1)=='-'))
              {s1=s1+2;e++;}
              else return false;
          }
          else return false;
        }     
        if(point<=1&&e<=1&&count>=1)return true;
        else return false;
        return true;        
    }
};