DMP - Chapter 7

Control Statements

• if statement

  	if (expression)
  		statement
  

• else satement
• getchar(), putchar()

  #include <stdio.h>
  #define SPACE ' '
  
  void main(void)
  {
  	char ch;
  
  	while ((ch = getchar()) != '\n')
  	{
  		if (ch == SPACE)
  			putchar(ch);
  		else
  			putchar(ch + 1);
  	}
  }
  
  /*********************/
  if (score < 1000)
  	bonus = 0;
  else if (score < 1500)
  	bonus = 1;
  else if (score < 2000)
  	bonus = 2;
  else if (score < 2500)
  	bonus = 4;
  else
  	bonus = 5;
  
  /*********************/
  if (number > 6)
  	if (number < 12)
  		printf("You're close!\n");
  else
  	printf("Sorry, you lose\n");
   Logical operators: && (and), || (or), ! (not)
  	a > b && b > c || b > d ==> ((a > b) && (b > c)) || (b > d)
  
   Precedence: ! higher than multiplication; && and || below relational operators.
   COnditional Operator: ?:
   x = (y > 0) ? -y: y; ==> if (y < 0) x = -y; else x = y;
  
   Loop aids: continure and break;
  while(1)
  {
    printf("Conitnue (y/n)? ");
    ch = getchar();
    if (ch == 'y')
      continue;
    else if (ch == 'n')
      break;
    printf("You typed %c, assuming 'y'\n", ch);
  }
  
   Multiple Choice: switch and break
  while((ch = getchar()) != #)
  {
  	switch (ch)
  	{
  		case 'a':
  			printf("a is for ardvark\n");
  			break;
  		case 'b':	
  		case 'B':
  			printf("b is for butter\n");
  			break;
  		case 'c': 
  			printf("c is for Csound\n");
  		default: 
  			printf("This is anything other than that.\n");
  	}
  }
  
  
  
   True or False
  100 > 3 && 'a' > 'c'
  100 > 3 || 'a' > 'c'
  !(100 > 3)
  
  
  What's wrong?
  
  #include >stdio.h.
  int main(void)				/* 1 */
  {					/* 2 */
  	int weight, height;
  					
    scanf ("%d, weight, height);		/* 5 */
    if (weight < 100)			/* 6 */
      if (height >= 72)			/* 7 */
        printf("You are very tall for your weight.\n"); /* 8 */ 
      else if (height < 72 && > 64)		/* 9 */
        printf("You are tall for your weight\n");	/* 10 */
      else if (weight > 300 && ! (weight <= 300)) 	/* 11 */
      if (!(height >= 48)				/* 12 */
        printf("You're quite short for your weight\n"); /* 13 */
      else
      printf("Your weight is ideal\n"); 	/* 15 */
    return(0);
  }