3.1 If-else branches (general)
3.1.12 If x equals -1 = Put "Disagrees" to output Else If x equals 0 = Put "Neutral" to output Else If x equals 1 = Put "Agrees" to output Else = Put "Invalid entry" to output ----------------------------------------------------------------------------- In the code above, suppose a programmer removed the "Else" part entirely. If x is 2, which is correct? 1.) The last branch, meaning the Else If x equals 1 branch, will execute. 2.) No branch will execute. 3.) The program is NOT legal.
2
3.1.12 If x equals -1 = Put "Disagrees" to output Else If x equals 0 = Put "Neutral" to output Else If x equals 1 = Put "Agrees" to output Else = Put "Invalid entry" to output In the code above, suppose a programmer, after the third branch (x equals 1), inserts a new branch: Else If x equals -1 ... When might that new branch execute? 1.) When x is -1 2.) When x is 1 3.) Never
3
3.1.12 If x equals -1 = Put "Disagrees" to output Else If x equals 0 = Put "Neutral" to output Else If x equals 1 = Put "Agrees" to output Else = Put "Invalid entry" to output If x is 1, then the output _________________.(Disagrees, Neutral, Agrees, or Invalid entry)
Agrees
A __________ is a program path taken only if an expression's value is true. Ex: A hotel may discount a price only for people over age 60. (Think of a tree)
Branch
3.1.12 If x equals -1 = Put "Disagrees" to output Else If x equals 0 = Put "Neutral" to output Else If x equals 1 = Put "Agrees" to output Else = Put "Invalid entry" to output If x is -5, then the output _________________.(Disagrees, Neutral, Agrees, Nothing is output, or Invalid entry)
Invalid entry
3.1.5 This program outputs the absolute value of the input. After getting input val, if val < 0, the branch val = -val executes. Finally, val is output. When executing, if the input val is -9, then val < 0 is true. The branch is taken, so val = -val executes, assigning val with 9. So 9 is output. If the input val were 45, will the branch be taken?
No
A restaurant host seats patrons. The host seats a party of 1 at the counter. A party of 2 is seated at a small table. Other size parties are seated at a large table. The host mentally executes the algorithm: "If party of 1, seat at counter; Else If party of 2, seat at small table; Else seat at large table." What if it was a party of 10?
Seat at large table
3.1.12 If x equals -1 = Put "Disagrees" to output Else If x equals 0 = Put "Neutral" to output Else If x equals 1 = Put "Agrees" to output Else = Put "Invalid entry" to output Could the programmer have written the three branches in the order: x equals 1, x equals 0, and x equals -1, and achieved the same results?
Yes