Chapter 2: [A] What would be the output of the following programs:

(a) 

main( )

{

    int   a = 300, b, c ;

    if ( a >= 400 )

    b = 300 ;

    c = 200 ;

    printf ( "\n%d %d", b, c ) ;

}

output

garbage-value 200

(b)

main( )

{

    int   a = 500, b, c ;

    if ( a >= 400 )

    b = 300 ;

    c = 200 ;

    printf ( "\n%d %d", b, c ) ;

}

output

200 300

(c)

main( ) 

{ 

    int x = 10, y = 20 ; 

    if ( x == y ) ; 

    printf ( "\n%d %d", x, y ) ; 

} 

output

10  20

(d)

main( ) 

{ 

   int x = 3, y = 5 ; 

   if ( x == 3 ) 

   printf ( "\n%d", x ) ; 

   else ; 

   printf ( "\n%d", y ) ; 

} 

output  

 

3 

5

(e) 

main( ) 

{ 

    int x = 3 ; 

    float y = 3.0 ; 

    if ( x == y ) 

    printf ( "\nx and y are equal" ) ; 

    else

    printf ( "\nx and y are not equal" ) ;

} 

output

x and y are equal

(g) 

main( ) 

{ 

   int k = 35 ; 

   printf ( "\n%d %d %d", k == 35, k = 50, k > 40 ) ; 

} 

output

0  50  0

(h)

main( ) 

{ 

int i = 65 ; 

char j = 'A' ; 

if ( i == j ) 

printf ( “C is WOW” ) ; 

else 

printf( "C is a headache" ) ; 

} 

output 

C is WOW 

(i) 

main( ) 

{ 

   int a = 5, b, c ; 

   b = a = 15 ; 

   c = a < 15 ; 

   printf ( "\na = %d b = %d c = %d", a, b, c ) ;

} 

output

a = 15 b = 15 c = 0

(j) 

main( ) 

{ 

   int x = 15 ; 

   printf ( "\n%d %d %d", x != 15, x = 20, x < 30 ) ; 

} 

output

1  20  1

Chapter 2: [B] Point out the errors, if any, in the following programs:

(a) 

main( )

{

    float   a = 12.25, b = 12.52 ;

    if ( a = b )

       printf ( "\na and b are equal" ) ;

}

No syntax error however logical error can occur due to missing relational operator == inside if condition.

 

 

(b)  

main( )

{

  int   j = 10, k = 12 ;

  if ( k >= j )

 {

   {

      k = j ;

      j = k ;

   }

 }

} 

No Error

(c)

main( )

{

    if ( 'X' < 'x' )

    printf ( "\nascii value of X is smaller than that of x" ) ;

} 

No Error

(d)  

 main( )

{

    int  x = 10 ;

    if ( x >= 2 ) then

       printf ( "\n%d", x ) ;

}

then is not a keyword in c

(e)

main( )

{

    int  x = 10 ;

    if x >= 2

       printf ( "\n%d", x ) ;

}

condition is not enclosed in braces 

  

(f)

main( )

{

    int  x = 10, y = 15 ;

    if ( x % 2 = y % 3 )

          printf ( "\nCarpathians" ) ;

}

Relational operator (==) is missing inside condition.

(g)

 

main( )

{

    int x = 30 , y = 40 ;

    if ( x == y )

       printf( "x is equal to y" ) ;

    elseif ( x > y ) 

       printf( "x is greater than y" ) ;

    elseif ( x < y )

       printf( "x is less than y" ) ;

}

There should be a space between else and if

(h) 

main( )

{

    int  x = 10 ;

    if ( x >= 2 ) then

       printf ( "\n%d", x ) ;

}

then is not a keyword in c.

(i)

main( )

{

    int a, b ;

       scanf ( "%d %d",a, b ) ;

    if ( a > b ) ;

       printf ( "This is a game" ) ;

    else

       printf ( "You have to play it" ) ;

}

& missing inside scanf