CSE 10 SUMMER 1997 
 
 MIDTERM EXAM:  DISCUSSION EXAMPLES

A) C++ FUNDAMENTALS (Given code segments)
1) Are these syntactically OK (will compile)?
   void fa (void) { cout << "hi"; /* ho */ }
   void fb (void) { cout << "hi"; // ho    }
   int main(void)
   {
   int         it      = 100, & r;
   const int   BIG;
   const int   BIGGER  = 10;
   const int   BIGGEST = it;
   it = BIGGER;
   BIGGER = it;
   }


B) LOOPS 
1)   Write a for loop to print the same output as while loop below.
 a)  Write a do  loop to print the same output as while loop below.
 b)  What gets printed if it was "while ( i = 5 )" instead ? 
  int i = 1;
  while ( i < 5 )
  { 
    ++i;
    cout << i << endl;
  }


C) DECISIONS
1) Write an if else to print same output as switch statement below. 
  int  i = 3, sum = 0 ;
  switch ( i )
  {
    case 1:
    case 2:
      sum++;
      break;
    case 3:
      sum--;
    default:
      cout <<  i <<  endl;
      break;
  }


D) FUNCTIONS
1) What is missing?  
  a) What gets printed now? 
  b) Is "i" in fn() same as in main()?
  c) Write fn() to be an inline function.
  d) Write fn() to be assigned a default initializer of 1.
  e) Write fn() to be an overloaded function accepting a formal parameter type 
     float.
  f) What makes an overloaded function?

#include 
int main(void)
{
   int i = 1;
   i = fn (i );
   cout << i << endl;
   cout << fn(i) << endl;
}
int fn ( int i ) { return(i + 2); }

2)  Are these legal?
int fn (int i = 0, int j, int k = 2);
fn (1, 2, int k = 3);


E) POINTERS
1) What gets printed?
#include 
void swap ( int *p, int *q );
void sort ( int *pA, int *pB);
int main ( void )      
{
  int dogA = 2, dogB = 4, *p, *q;
  p = &dogA; 
  q = &dogB;
  cout << *p * 2 << "  " << 4 * *p << "  " << *q  -  *p << endl;
  sort( &dogA, &dogB );
  cout << dogA << " " << dogB << endl;
  return 0;
}

void swap ( int *p, int *q )
{ int tmp;    tmp = *p;    *p  = *q;    *q  = tmp ; }

void sort ( int *pA, int *pB ) { if ( *pA < *pB ) swap (pA, pB); }


F) REFERENCE TYPES
1) What gets printed?
   int  i = 3, &r = i;
   ++i;
   cout << i << "  " << r << endl;

2) What gets printed?
#include 
inline void fn ( int & r ) { r = 2; }
int main(void)
{
   int i = 1;
   fn (i);
   cout << i << endl;
   return 0;
}


G)  C++ ARRAYS
1)What gets printed?  
#include 
void fn(int a1[]);
void swap(int & r1, int & r2);
int main ( void )      
{ 
  int i, qa[] = {7, 8, 9}; 
  fn(qa);
  return 0;
}

void fn( int a1[] )
{
  int i, j;
  for ( i = 0 ; i < 3 ; ++i )
    for ( j = i + 1; j < 3 ; ++j )
      if ( a1[i] < a1[j] )
      {
         swap ( a[i], a[j] );
         cout << a[i]  << "  " << a[j] << endl;
      }
  cout << endl;
}
 
void swap(int &r1, int &r2)
{ int tmp;    tmp = r1;    r1  = r2;    r2  = tmp; }


H)  C++ NULTI-D ARRAYS
1) How would you handle 3-D array? (3 for loops)  What gets printed?
#include 
void fill ( int jet[][2]);
void save ( int st );
int main ( void )      
{
  int i, j, plane[3][2] = { 1, 1, 1, 2, 2, 2};
  fill ( plane );
  save ( plane[0][0] );        
  for (i = j = 0; i < 3 ; ++i )
    cout << plane[i][j] << endl;
  return 0;
}

void fill ( int jet[][2] )
{
  int i, j;
  for ( i = 0 ; i < 3 ; ++i )
    for ( j = 0 ; j < 2 ; ++j )
       if ( i == 0 || j == 0 )
         jet[i][j] *= 2;
}

void save ( int st ) { st = 99; }