DLCS test quiz

The table below shows the time a computer system takes to complete a specified task on the customer data of different-sized companies. Based on the information in the table, which of the following tasks is likely to take the longest amount of time when scaled up for a very large company of approximately 100,000 customers?

• Backing up data
• Deleting entries from data
• Searching through data
• Sorting data

A programmer completes the user manual for a video game she has developed and realizes she has reversed the roles of goats and sheep throughout the text. Consider the programmer’s goal of changing all occurrences of “goats” to “sheep” and all occurrences of “sheep” to “goats.” The programmer will use the fact that the word “foxes” does not appear anywhere in the original text. Which of the following algorithms can be used to accomplish the programmer’s goal?

• First, change all occurrences of “goats” to “sheep.” Then, change all occurrences of “sheep” to “goats.”
• First, change all occurrences of “goats” to “sheep.” Then, change all occurrences of “sheep” to “goats.” Last, change all occurrences of “foxes” to “sheep.”
• First, change all occurrences of “goats” to “foxes.” Then, change all occurrences of “sheep” to “goats.” Last, change all occurrences of “foxes” to “sheep.”
• First, change all occurrences of “goats” to “foxes.” Then, change all occurrences of “foxes” to “sheep.” Last, change all occurrences of “sheep” to “goats.”

There are 32 students in a classroom. Two different algorithms are given for finding the average height of the students. Algorithm A Step 1: All students stand. Step 2: A randomly selected student writes his or her height on a card and is seated. Step 3: A randomly selected standing student adds his or her height to the value on the card, records the new value on the card, and is seated. The previous value on the card is erased. Step 4: Repeat step 3 until no students remain standing. Step 5: The sum on the card is divided by 32. The result is given to the teacher. Algorithm B Step 1: All students stand. Step 2: Each student is given a card. Each student writes his or her height on the card. Step 3: Standing students form random pairs at the same time. Each pair adds the number written on their cards and writes the result on one student’s card; the other student is seated. The previous value on the card is erased. Step 4: Repeat step 3 until one student remains standing. Step 5: The sum on the last student’s card is divided by 32. The result is given to the teacher. Which of the following statements is true?

• Algorithm A always calculates the correct average, but Algorithm B does not.
• Algorithm B always calculates the correct average, but Algorithm A does not.
• Both Algorithm A and Algorithm B always calculate the correct average.
• Neither Algorithm A nor Algorithm B calculates the correct average

Under which of the following conditions is it most beneficial to use a heuristic approach to solve a problem?

• When the problem can be solved in a reasonable time and an approximate solution is acceptable
• When the problem can be solved in a reasonable time and an exact solution is needed
• When the problem cannot be solved in a reasonable time and an approximate solution is acceptable
• When the problem cannot be solved in a reasonable time and an exact solution is needed

FOUR INDEPENDENT ALGORITHMS listed below can be executed on a row of NUMBER cards (Not FACE cards) on a table. There are an EVEN number of cards, and they are in no special order. Which of the Algorithms involves BOTH Selection and Iteration? For this question select TWO correct answers

• Look over all the cards to find the smallest one, and move it to the leftmost position.
• Compare the first two cards. If the one on the left is greater, switch them.
• Compare the values of each pair of cards. For example, compare cards 0 and 1, compare cards 2 and 3, and so on for all pairs. Swap positions when the first card is greater than the second of the pair.
• Find the middle card and switch it with the card in the rightmost position.