IPA FE Subject A sample Question 6

Question

When the flowchart in Figure 1 was executed with array A in the state shown in Figure 2, array B came to be in the state shown in Figure 3. Which of the following is the operation to be inserted into blank a in Figure 1? Here, the elements of arrays A and B are A(i, j) and B(i, j), respectively.

[Figure: Figure 1, a flowchart, top to bottom: Start; the loop start “Loop 1” with i: 0,1,7 (Note); the loop start “Loop 2” with j: 0,1,7 (Note); a process box containing blank a; the loop end “Loop 2”; the loop end “Loop 1”; End.]

Figure 1  Flowchart

(Note) The repetition specification of a loop limit shows variable name: initial value, increment, final value.

[Figure: Figure 2, array A as an 8 × 8 grid, rows i = 0 to 7 down the left, columns j = 0 to 7 across the top. Asterisks: row 0, columns 1 to 6; column 1, every row from 0 to 7; row 3, columns 1 to 4. All other cells are empty (an F shape).]

Figure 2  State of array A

[Figure: Figure 3, array B after execution as an 8 × 8 grid, rows i = 0 to 7 down the left, columns j = 0 to 7 across the top. Asterisks: row 1, every column from 0 to 7; column 4, rows 2 to 4; column 7, rows 2 to 6. Row 0, row 7 and all other cells are empty.]

Figure 3  State of array B after execution

Accepted Answer

d) B(j, 7 − i) ← A(i, j)

Answer

a) B(7 − i, 7 − j) ← A(i, j)

Answer

b) B(7 − j, i) ← A(i, j)

Answer

c) B(i, 7 − j) ← A(i, j)

Explanation