D. Do the online reading: Overloading the plus operator, doing the next set of questions while you do so. 1. 11 + 22 evaluates to: (NOTE: write error if evaluating the expression generates an error.) ANS. 33 2. '11' + '22' evaluates to: (NOTE: write error if evaluating the expression generates an error.) ANS. '1122' ANS. 1122 ANS. "1122" 3. '11' + str(3 + 3) + '22' evaluates to: (NOTE: write error if evaluating the expression generates an error.) ANS. '11622' ANS. "11622" ANS. 11622 4. '11' + 33 evaluates to: (NOTE: write error if evaluating the expression generates an error.) ANS. error ANS. ERROR 5. What does the following code snippet print:

 x = 1 
 y = 2 
 z = 3 
 print(x, y, z)

a. 1, 2, 3 b. 1 2 3~ c. 6 d. 123 6. What does the following code snippet print:

 x = 1 
 y = 2 
 z = 3 
 print(str(x) + str(y) + str(z))

a. 1, 2, 3 b. 1 2 3 c. 6 d. 123~ 7. What does the following code snippet print:

 x = 1 
 y = 2 
 z = 3 
 print(x + y + z)

a. 1, 2, 3 b. 1 2 3 c. 6~ d. 123 8. What does the following code snippet print:

 x = 1 
 y = 2 
 z = 3 
 print(str(x + y) + str(z))

ANS. 33 9. Implement a function named print_equation that given two numbers x and y, prints an equation for the sum of them. For example, if x is 65 and y is 11, the function would print 65+11=76. M. Line 1 -> def print_equation(x, y): M. Line 2 -> print(str(x) + "+" + str(y) + "=" + str(x+y)) M. -> print(x, y, x+y) M. -> print(x+++y+ = +x+y) M. -> print("65+11=76") D. Do the online reading: Accumulating Sequences, doing the next set of questions while you do so. D. On a piece of paper (NOT here in Moodle), implement the following function, per its doc-string. You do NOT have to be completely correct, just try to get the main idea correct, with guidance from the reading. After you have made a reasonable try, turn to the next page in this Moodle quiz for a solution.

def make_simple_list(m, n):
    """
    Returns the list [m, m+1, m+2, ... n],
    where m and n are the given arguments.
    For example, if m is 5 and n is 13,
    then this function returns:
        [5, 6, 7, 8, 9, 10, 11, 12, 13]
    """

D. Here is a solution to the previous problem. Compare your solution to it. Bring any questions about this problem to class.

def make_simple_list(m, n):
    """ Same specification as on the previous item. """
    seq = []
    for k in range(m, n + 1):
        seq = seq + [k]
    return seq

1. Consider the following code. What should the missing statement be (that is, the statement marked ???).

def make_list(n):
    """
    Returns the list [1, 2, 3, ... n],
    where n is the given argument.
    For example, if n is 5,
    then this function returns:
        [1, 2, 3, 4, 5]
    """
    seq = []
    for k in range(n):
        ???
    return seq

a. seq = seq[k] a. seq = seq[k + 1 ] b. seq = seq + k b. seq = seq + k + 1 c. seq = seq[k] + [k] d. seq[k] = seq[k] + [k] e. seq = seq + [k + 1]~ e. seq = seq + seq[k] e. seq = seq + seq[k + 1] 2. What does the following code snippet print: (Note: If your answer includes any commas, put a SINGLE SPACE after each comma, to help out the automated grading. But no problem if you get the right answer except for spaces.)

 x = 0 
 for k in range(5): 
     x = x + (2 * k) 
 print(x)

ANS. 20 2. What does the following code snippet print: (Note: If your answer includes any commas, put a SINGLE SPACE after each comma, to help out the automated grading. But no problem if you get the right answer except for spaces.)

 x = [] 
 for k in range(5): 
     x = x + [(2 * k)] 
 print(x)

ANS. [0, 2, 4, 6, 8] 2. What does the following code snippet print: (Hint: ignore the comma in the code, but ask in class why it is necessary.) (Note: If your answer includes any commas, put a SINGLE SPACE after each comma, to help out the automated grading. But no problem if you get the right answer except for spaces.)

 x = () 
 for k in range(5): 
     x = x + ((2 * k),) 
 print(x)

ANS. (0, 2, 4, 6, 8) 2. What does the following code snippet print: (Note: If your answer includes any commas, put a SINGLE SPACE after each comma, to help out the automated grading. But no problem if you get the right answer except for spaces.)

 x = '' 
 for k in range(5): 
     x = x + str(2 * k) 
 print(x)

ANS. 02468 ANS. '02468' ANS. "02468" D. In the above question, make sure that you understand why applying the built-in str function is necessary. D. Watch the video: Sequences, doing the next set of questions while you do so. D. For the next set of questions, consider the following three function definitions:

def foo1(seq):
    total = 0
    for k in range(len(seq) // 2):
        total = total + seq[1 + (2 * k)]
    return total


def foo2(seq):
    total = 0
    for k in range(1, len(seq), 2):
        total = total + seq[k]
    return total


def foo3(seq):
    total = 0
    m = 1
    for _ in range(len(seq) // 2):
        total = total + seq[m]
        m = m + 2
    return total

1. To what number does foo1([3]) evaluate? a. 0~ b. 1 c. 2 d. 3 e. 4 f. 5 g. 6 h. 7 i. 8 j. 9 k. 10 l. 11 m. 12 n. 13 o. 14 p. 15 q. 16 r. 17 r. 18 r. 19 r. 20 r. 24 r. 33 r. 38 1. To what number does foo1([3, 6]) evaluate? a. 0 b. 1 c. 2 d. 3 e. 4 f. 5 g. 6~ h. 7 i. 8 j. 9 k. 10 l. 11 m. 12 n. 13 o. 14 p. 15 q. 16 r. 17 r. 18 r. 19 r. 20 r. 24 r. 33 r. 38 1. To what number does foo1([3, 6, 1, 4, 9, 5]) evaluate? a. 0 b. 1 c. 2 d. 3 e. 4 f. 5 g. 6 h. 7 i. 8 j. 9 k. 10 l. 11 m. 12 n. 13 o. 14 p. 15~ q. 16 r. 17 r. 18 r. 19 r. 20 r. 24 r. 33 r. 38 1. To what number does foo2([3]) evaluate? a. 0~ b. 1 c. 2 d. 3 e. 4 f. 5 g. 6 h. 7 i. 8 j. 9 k. 10 l. 11 m. 12 n. 13 o. 14 p. 15 q. 16 r. 17 r. 18 r. 19 r. 20 r. 24 r. 33 r. 38 1. To what number does foo2([3, 6]) evaluate? a. 0 b. 1 c. 2 d. 3 e. 4 f. 5 g. 6~ h. 7 i. 8 j. 9 k. 10 l. 11 m. 12 n. 13 o. 14 p. 15 q. 16 r. 17 r. 18 r. 19 r. 20 r. 24 r. 33 r. 38 1. To what number does foo2([3, 6, 1, 4, 9, 5]) evaluate? a. 0 b. 1 c. 2 d. 3 e. 4 f. 5 g. 6 h. 7 i. 8 j. 9 k. 10 l. 11 m. 12 n. 13 o. 14 p. 15~ q. 16 r. 17 r. 18 r. 19 r. 20 r. 24 r. 33 r. 38 1. To what number does foo3([3]) evaluate? a. 0~ b. 1 c. 2 d. 3 e. 4 f. 5 g. 6 h. 7 i. 8 j. 9 k. 10 l. 11 m. 12 n. 13 o. 14 p. 15 q. 16 r. 17 r. 18 r. 19 r. 20 r. 24 r. 33 r. 38 1. To what number does foo3([3, 6]) evaluate? a. 0 b. 1 c. 2 d. 3 e. 4 f. 5 g. 6~ h. 7 i. 8 j. 9 k. 10 l. 11 m. 12 n. 13 o. 14 p. 15 q. 16 r. 17 r. 18 r. 19 r. 20 r. 24 r. 33 r. 38 1. To what number does foo3([3, 6, 1, 4, 9, 5]) evaluate? a. 0 b. 1 c. 2 d. 3 e. 4 f. 5 g. 6 h. 7 i. 8 j. 9 k. 10 l. 11 m. 12 n. 13 o. 14 p. 15~ q. 16 r. 17 r. 18 r. 19 r. 20 r. 24 r. 33 r. 38 D. For the next set of questions, consider the following two attempts at a function that returns the first negative item in the sequence of numbers, or None if the sequence contains no negative numbers. One function is correct and the other is wrong.

def find1(numbers):
    for k in range(len(numbers)):
        if numbers[k] < 0:
            return numbers[k]
        else:
            return None


def find2(numbers):
    for k in range(len(numbers)):
        if numbers[k] < 0:
            return numbers[k]
    return None

1. What gets returned by the function call find1( [-3, 6, 1, 4, 9, 5] )? ANS. -3 1. What gets returned by the function call find2( [-3, 6, 1, 4, 9, 5] )? ANS. -3 1. What gets returned by the function call find1( [3, 6, 1, 4, 9, 5] )? ANS. None 1. What gets returned by the function call find2( [3, 6, 1, 4, 9, 5] )? ANS. None 1. What gets returned by the function call find1( [3, -6, 1, 4, 9, 5] )? ANS. None 1. What gets returned by the function call find2( [3, -6, 1, 4, 9, 5] )? ANS. -6 1. Which attempt is correct? a. find1 b. find2~ D. IMPORTANT: Be sure that you understand the previous problem and its answer! Bring questions to class!