The problem presents a flowchart that evaluates a student's answers to 40 questions. The task is to determine the values for the labels P, Q, R, and S in the flowchart. Also we must identify the type of nested control structure used and write the corresponding pseudocode. The flowchart uses an array named "ans" that stores the correct answers. Qno represents the question number, and Total represents the total marks obtained.
2025/7/27
1. Problem Description
The problem presents a flowchart that evaluates a student's answers to 40 questions. The task is to determine the values for the labels P, Q, R, and S in the flowchart. Also we must identify the type of nested control structure used and write the corresponding pseudocode. The flowchart uses an array named "ans" that stores the correct answers. Qno represents the question number, and Total represents the total marks obtained.
2. Solution Steps
* P: This label is within a decision diamond, so it must contain a condition. The loop continues as long as there are questions to be checked. Therefore, P is the upper limit of the number of questions. Since there are 40 questions, P must be
4
0.
* Q: This label appears on the "Yes" exit from the decision diamond at P. The logic within the flowchart tells us that when the condition at P is no longer true, the flowchart should terminate. Therefore, Q is the terminal node and the value would be Stop.
* R: This label represents where the answer is input by the student.
* S: This label appears in the assignment statement `Total = Total + (S)`. This step increments the total score. Since the increment occurs only when the student's answer matches the value in the ans array for the current question, S represents the value added for a correct answer, which is
1.
* Type of nested control structure: The flowchart contains a loop (checking each question) and a conditional statement within the loop (checking if the answer is correct). This represents a nested control structure where the conditional statement `If` statement lies inside the `While` loop.
* Pseudocode:
```
START
Total = 0
Qno = 1
WHILE Qno <= 40
INPUT Answer
IF Answer == ans[Qno] THEN
Total = Total + 1
ENDIF
Qno = Qno + 1
ENDWHILE
DISPLAY Total
STOP
```
3. Final Answer
(i)
P: 40
Q: Stop
R: Answer
S: 1
(ii)
Nested control structure: While loop with an If statement inside.
(iii)
Pseudocode:
```
START
Total = 0
Qno = 1
WHILE Qno <= 40
INPUT Answer
IF Answer == ans[Qno] THEN
Total = Total + 1
ENDIF
Qno = Qno + 1
ENDWHILE
DISPLAY Total
STOP
```