atoi和itoa函数

以下是我自己写的atoi()和itoa() 

int atoi(const char *string)
{
     int i = 0;
     int value = 0;
     while(string[i]!='/0')
     {
          value = value*10 + string[i] -'0';
          i++;
     }  
     return value; 
}

 

void itoa(int value, char *string, int radix) 
{
     if((radix > 1)&&(radix < 11))
     {
           int i = 0;
           int len = 0;
           char *temp;
           while(value > 0)
           {
                temp[len++] = value % radix + '0';
                value = value / radix;           
           }
           for(i=0;i<len;i++)
           {
                string[i] = temp[len-i-1];       
           }
           string[i] = '/0';
     }
     else return;    
}