Here are 6 different versions of function findDigit with the same pre- and post- conditions.
Trace with some or all of the following data:
findDigit (30568,2);
findDigit (324,5);
findDigit(-4532,3)

1. int findDigit(int num, int place)
   //  pre : num is a valid integer;   place >= 1
   //  post: findDigit returns the value in the position place
   {
   	int dividend = 10;
   	for (int count = 1; count < place; count++)
   		dividend = dividend * 10;
   	num = num / dividend;
   	return (num % 10);
   }

   
   Does it work?________If not what is the problem? If it works, is there any test data that would not work?

2. int findDigit(int num, int place)
   {
   	int divide = 1;
   	for (int count = 2; count <= place; count ++)
   		divide = divide * 10;
   	return (num / divide);
   {

   
   Does it work?________If not what is the problem? If it works, is there any test data that would not work?

3. assume power function works
   

   int findDigit ( int num, int place)
   {
   	return (int) num / power (10,place+1)/ power(10,place);
   }

   
   Does it work?________If not what is the problem? If it works, is there any test data that would not work?

4. int findDigit ( int num, int place)
   {
   	double result = num;
   	for (int count = 1; count <= place; count++)
   		result = result - 1;
   	while (result >= 1)
   		result = result - 1;
   	return int( result * 10);
   }

   
   Does it work?________If not what is the problem? If it works, is there any test data that would not work?

5. int findDigit(int num, int place)
   {
   	int count = 1;
   	int x = abs(num);
   	while ((x >= 10) && (count != place))
   	{
   		count ++;
   		x = x / 10;
   	}
   	if (count == place)
   		return (x % 10);
   	else return 0;
   }

   
   Does it work?________If not what is the problem? If it works, is there any test data that would not work?

6. int findDigit (int num, int place)
   {
   	if (place == 1)
   		return (num % 10);
   	return (findDigit (num / 10, place -1);
   {

   
   Does it work?________If not what is the problem? If it works, is there any test data that would not work?

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