new solution of GetInt(char *strint, int val)

There are some improvements in Cong Wang's solution of the first challenge.

1. it does not handle negative integer
2. it does not handle integer zero

Cong Wang's solution
==============================================
void GetInt(char *strint, int val){

char rev[100];

int length=0;

while (val > 0)
{
int a = val % 10;
rev[length++] = a | '0';
val /= 10;
}
rev[length]='\0';


length--;
int rev = 0;
while (length >= 0)
{
strint[rev++] = rev[length--];
}

strint[rev] = '\0';
}
==============================================


my new solution
==============================================

void GetInt(char *strint, int val) {
   int len = 0;
   bool negative = false;

   if(val < 0) { // if negative           
      val = -val;        
      negative = true;    
   } else if (val == 0) {         // if 0
      strint[len++] = '0';    
   }     

   while (val > 0) {
      strint[len++] = (val % 10) + '0';
      val /= 10;
   }

   if(negative) {
      strint[len++] = '-';
   }

   // reverse this string
   for(int i=0; i < len /2; i++) {
      char a = strint[i];
      strint[i] = strint[len-1-i];
      strint[len-1-i] = a;
   }

   strint[len] = '\0';
}