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Switch Statments

Let's say you wish to write a program that will calculate a person's letter grade based on their test scores. You could do it like this:
#include<iostream.h>
void main()
{
	int score;
	cout « "Enter the test score: "« endl;
	cin» score;
	if(score>100) cout « "out of range" « endl;
	else if (score>=90) cout«'A'« endl;
	else if (score>=80) cout«'B'« endl;
	else if (score>=70) cout«'C'« endl;
	else if (score>=60) cout«'D'« endl;
	else if (score>=0)  cout«'F'« endl;
	else cout« "Error: score out of range."« endl;
}
When you start to use a lot of else if statements, your program can look a little confusing. Another way to do the same thing is to use the switch statement. A switch statement looks like this:

switch(choice)
 {
   case 1: statement; break;
   case 2: statement; break;
   case 3: statement; break;
 }
You offer the user a series of choices and the program offers a response based on their choice. Here's how we can re-do our grade program using switch statements:

#include<iostream.h>
void main()
{
	int score;
	cout« "Enter the test score: "« endl;
	cin» score;
	switch(score/10){
	case 10: 
	case 9: cout«'A'« endl; break;
	case 8: cout«'B'« endl; break;
	case 7: cout«'C'« endl; break;
	case 6: cout«'D'« endl; break;
	case 5: 
	case 4: 
	case 3: 
	case 2: 
	case 1: 
	case 0: cout«'F'« endl; break;
	default: cout«"Error: score out of range."« endl;
	}
}
You can use switch statements do all sorts of things. Here's an example of using switch statments of create a menu: 
#include<iostream.h>
void main()
{
	char letter;

	cout«"\t\t\t--------------MENU-------------"« endl;
	cout«"\t\t\t-----A: first menu item--------"« endl;
	cout«"\t\t\t-----B: first menu item--------"« endl;
	cout«"\t\t\t-----C: first menu item--------"« endl;
	cout«"\t\t\t-----D: first menu item--------"« endl;
	cout«"\t\t\t-----E: first menu item--------"« endl;
	cout«"\t\t\tEnter a capital letter to select one"« endl;
	

	cin» letter;

	switch(letter){
	case 'A': cout«"The first was selected."« endl; break; 
	case 'B': cout«"The second was selected."« endl; break;
	case 'C': cout«"The third was selected."« endl; break;
	case 'D': cout«"The fourth was selected."« endl; break;
	case 'E': cout«"The fifth was selected."« endl; break;
	
	
	default: cout« "You didn't pick one."« endl;
	}
}
Assignment

Write a program that displays the signs of the horoscope. Create a series of whacky responses to match whatever choice they made. Due: Feb 21.