Spring 1995	MidSemester Exam (100pts)	Name________________________

1.(4pts)	  Does the following assignment always correctly store 
the average of the three int objects a, b, 
and c into ave <yes/no> _______?
*** No

	float ave = (a+b+c/3.0);

2.(7pts)    Circle only the valid identifiers that follow:

	main   cin   A    1a    A_1    M/H    coarse_describbles
*** main  cin  A  A_1  coarse_describbles


3. (8pts)   Place circles for each error that would result in compiletime 
error

	#include <math.h
	int main
 	{
	  integer j = 0
	  cout << "Hello", j;	
	  cin >> x;
        return 0;
*** should be (with *** marking lines with errors):
	#include <iostream.h>***
	#include <math.h>***
	int main()***
 	{
	  int x = 0;***
	  int j = 0;******
	  cout << "Hello" << j;***	
	  cin >> x;***
        return 0;
	}***
4. (4pts)	Write a single assignment statement that changes the 
value of cost by adding a 17.5% tax to cost. 
The increase must be correct for any initial value of cost, not just 100.00.

	float cost = 100.00;
***
	cost = 1.175*cost;
or	cost = cost + .175*cost;
or	cost *= 1.175;



5. (10pts)	Write the output generated by the following program:
#include <iostream.h>
#include "ouracct.h"   // for class bankAccount
int main()
{
  bankAccount Kay("Missie", "9876", 100.00);
  cout << Kay.name() << "  " << Kay.PIN() << endl;
  cout << Kay.balance() << endl;
  Kay.deposit(23.45);
  cout << Kay.balance() << endl;
  Kay.withdraw(50.00);
  cout << Kay.balance() << endl;
  return 0;
}
***
MISSIE  9876
100
123.45
73.45


6. (10pts)	Complete this program that constructs one bankAccount 
object using any data you desire. Then make a deposit of 55.44, a 
withdrawal of 20.00, and then show the balance.
#include <iostream.h>
#include "ouracct.h"   // for class bankAccount
#include "ourstr.h"    // for class string
int main()
{
***
  bankAccount Kay("Missie", "9876", 100.00);
  Kay.deposit(55.44);
  Kay.withdraw(20.00);
  cout << Kay.balance() << endl;
  return 0;
}


7. (12pts)     Given this function prototype with postconditions, determine 
the following information

double diff(double a, double b);
// POST: Returns the positive difference between a and b

a. return type:
***
double
b. function name:
***
diff
c. number of arguments:
***
2
d. data type of arguments:	
***
double
e. Write a valid call to diff with constant arguments:
***
diff(3.2, 8.5);
f. What is the return value of your function call?
***
5.3

8. (6pts)    Circle the letters representing valid function prototypes 
assuming no #include directives.

a. int large(int a; int b;);		   d. int f(int b);
b. double c(double a, double b);    e. void show(float x);
c. large_int(a, b);		   f. character c(int a);
***
b,  d,  and e are valid

9. (5pts)    Write the output from the following program:
	#include <iostream.h>

double monthlyFee(int checks, int atms)
{
  return(checks * 0.25 + atms * 0.10);
}

int main()
{
  cout << "fee: " << monthlyFee(20, 10) << endl;
	  return 0;
}
***
fee: 6

10a. (2pts)  Write the name of the class given below.

***
doLittle

10b. (4pts)  Write the names of the member functions.

***
doLittle  huh

10c. (4pts)  Write the names of the data members.

***
a   b

10d. (4pts)  Write the output generated by this program.

***
85   80

#include <iostream.h>

class doLittle {
public:
  doLittle(int initA, int initB);
  int huh();
private:
  int a, b;
};

doLittle::doLittle(int initA, int initB)
{
  a = initA;
  b = initB;
}

int doLittle::huh()
{
  return ((a + b)/2);
}

int main()
{
  doLittle one(80, 90), two(75, 85);
  cout << one.huh() << "  " << two.huh() << endl;
  return 0;
}



11. (9pts)   Write the output generaterd by the following program
#include <iostream.h>
#include "ourstr.h"
string huh(int n)
{
  if(n < 10)
    return "low";
  else if(n < 20)
    return "mid";
  else
    return "high";
}

int main()
{
  cout << huh(15) << endl;
  cout << huh(8) << endl;
  cout << huh(45) << endl;
  return 0;
}

***
mid 
low
high


12. (11pts)   Write a complete function that returns the larger of any 
three numeric values that have been received as value parameters. 
The following function call must be valid and also return 87: 

	larger(75, 87, 63);
***
double larger(double A, double B, double C)
{
if((A>=B) && (A>=C))  return A;
if(B>=C) return B;  // must be B or C at this point
return C;
}


CSCI-15A	Jim Murphy	Page 4