Paper C: December 2024 (Solved)

Analysis of the APJ Abdul Kalam Technological University B.Tech Degree S1 (Challenge Course) Examination questions.

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Part A (Identity & Loops)

1. Valid Identifiers

Criteria: mark1 (Valid), _123 (Valid), $price (Invalid - Symbol), rank list (Invalid - Space), -name (Invalid - Operator).

6. Static Count Behavior

Question: static int count = 0; count++; called 5 times. Solution: Since count is static, its value persists between calls. Output: 1, 2, 3, 4, 5.

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Part B (Program Logic)

Q9a. Expression Trace

int a=5, b=8, c=9, d;
d = a++ + --b + c++;
// 5 + 7 + 9 = 21 (Result)
// Final State: a=6, b=7, c=10

Q10a. Bitwise Bit Counting

Counting '1' bits using num & 1.

int countOnes(int n) {
    int count = 0;
    while(n > 0) {
        if(n & 1) count++;
        n >>= 1;
    }
    return count;
}

Q11b. Bubble Sort (Descending)

Sorting in reverse order using a[j] < a[j+1].

Q12b. Manual Palindrome Check

Checking if a string is a palindrome without using strrev() or strcmp().

int isPalindrome(char s[], int len) {
    for(int i=0; i < len/2; i++) {
        if(s[i] != s[len-1-i]) return 0;
    }
    return 1;
}

Q14a. Student Struct & Grading

Implementing a structure for student records and assigning grades (O, A, B, etc.) based on percentage thresholds $(90, 80, 70 dots)$.

Q16b. Stock Reorder Logic

Reading stock data and printing items where quantity < reorder_level.