ex2-1.c

/* code: ex2-1.c   (v1.20.00) */
#include <stdio.h>

int main ()
{
  int x, y;

  x = 500;
  y = 300;

  printf ("X = %d\n", x);
  printf ("Y = %d\n", y);

  if (x > y)
    printf ("X is greater than Y.\n");


  return 0;
}

ex2-2.c

/* code: ex2-2.c   (v1.20.00) */
#include <stdio.h>

int main ()
{
  int x, y;
  x = 500;
  y = 700;
  printf ("X = %d\n", x);
  printf ("Y = %d\n", y);

  if (x > y)
    printf ("X is greater than Y.\n");
  else
    printf ("X is less than or equal to Y.\n");

  return 0;
}

ex2-3.c

/* code: ex2-3.c   (v1.20.00) */
#include <stdio.h>

int main ()
{
  char grade;

  grade = 'B';

  switch (grade) {
  case 'A':
    printf ("excellent\n");
    break;
  case 'B':
    printf ("good\n");
    break;
  case 'C':
    printf ("fair\n");
    break;
  case 'D':
    printf ("barely passing\n");
    break;
  case 'F':
    printf ("not passing\n");
    break;
  default:
    printf ("ERROR: invalid character\n");
    break;
  }
  printf ("Your grade is  %c\n", grade);
  return 0;
}

q2-1.c

/* code: q2-1.c   (v1.20.00) */
#include <stdio.h>

int main ()
{
  int x, y;

  printf ("enter X: ");
  scanf ("%d", &x);
  printf ("enter Y: ");
  scanf ("%d", &y);

  printf ("X = %d\n", x);
  printf ("Y = %d\n", y);

  if (x > y) {
    printf ("X is greater than Y.\n");
  }
  else {
    printf ("X is less than or equal to Y.\n");
  }

  return 0;
}

q2-2.c

/* code: q2-2.c   (v1.20.00) */
#include <stdio.h>

int main ()
{
  char grade;

  grade = 'b';

  switch (grade) {
  case 'a':
  case 'A':
    printf ("excellent\n");
    break;
  case 'b':
  case 'B':
    printf ("good\n");
    break;
  case 'c':
  case 'C':
    printf ("fair\n");
    break;
  case 'd':
  case 'D':
    printf ("barely passing\n");
    break;
  case 'f':
  case 'F':
    printf ("not passing\n");
    break;
  default:
    printf ("ERROR: invalid character\n");
    break;
  }
  printf ("Your grade is  %c\n", grade);
  return 0;
}

q2-3.c

/* code: q2-3.c   (v1.20.00) */
#include <stdio.h>

int main ()
{
  int a;
  a = 3;

  if (a == 0 || a == 1 || a == 2) {
    printf ("A\n");
  }
  else if (a == 3 || a == 4) {
    printf ("B\n");
  }
  else {
    printf ("ERROR: invalid number\n");
  }

  return 0;
}

q2-3a.c

/* code: q2-3a.c   (v1.20.00) */
#include <stdio.h>

int main ()
{
  int a;
  a = 3;
  switch (a) {
  case 0:
  case 1:
  case 2:
    printf ("A\n");
    break;
  case 3:
  case 4:
    printf ("B\n");
    break;
  default:
    printf ("ERROR: invalid number\n");
    break;
  }

  return 0;
}