1. Problem: Verify the algorithm that classifies numbers as "Single Digit", "Double Digit", or "Big" for the inputs (5, 9, 47, 99, 100, 200). 2. The original algorithm is: IF Number < 9 PRINT "Single Digit" ELSE IF Number < 99 PRINT "Double Digit" ELSE PRINT "Big" 3. Check each input: - For 5: 5 < 9, so "Single Digit" (correct) - For 9: 9 < 9 is false, 9 < 99 is true, so "Double Digit" (correct) - For 47: 47 < 9 false, 47 < 99 true, "Double Digit" (correct) - For 99: 99 < 9 false, 99 < 99 false, so "Big" (incorrect, 99 is two digits) - For 100: 100 < 9 false, 100 < 99 false, "Big" (correct) - For 200: similarly "Big" (correct) 4. The problem is with the boundary conditions: 9 and 99. 5. Corrected algorithm: IF Number <= 9 PRINT "Single Digit" ELSE IF Number <= 99 PRINT "Double Digit" ELSE PRINT "Big" 6. This includes 9 and 99 correctly. 7. Implementation in C: ```c #include int main() { int Number; printf("Enter a number: "); scanf("%d", &Number); if (Number <= 9) { printf("Single Digit\n"); } else if (Number <= 99) { printf("Double Digit\n"); } else { printf("Big\n"); } return 0; } ``` --- 1. Problem: Algorithm to accept only positive integers up to 100. 2. Original algorithm: IF (0 < Number) AND (Number <= 100) PRINT "ACCEPT" ELSE PRINT "REJECT" 3. Values where it fails: - Number = 0: 0 is not > 0, so rejected (correct if zero is not accepted) - Negative numbers: rejected (correct) - Numbers > 100: rejected (correct) - Non-integer inputs: algorithm does not handle non-integers 4. Improvement: - Explicitly check if Number is an integer. - Clarify if zero is accepted or not. 5. Improved algorithm: IF Number is integer AND (1 <= Number <= 100) PRINT "ACCEPT" ELSE PRINT "REJECT" --- 1. What is a function? A function is a block of code designed to perform a specific task, which can be called and reused in a program. 2. Need for functions: Functions help organize code, avoid repetition, improve readability, and facilitate debugging and maintenance. 3. Actual parameter vs Formal argument: - Actual parameter: the real value or variable passed to a function when called. - Formal argument: the variable defined in the function declaration to receive the actual parameter. 4. Function prototype: A declaration of a function that specifies its name, return type, and parameters without the body, informing the compiler about the function. 5. Call by value vs Call by reference: - Call by value: passes a copy of the argument; changes inside the function do not affect the original. - Call by reference: passes the address; changes inside the function affect the original variable. 6. Steps in writing a function: - Define the function prototype. - Write the function definition. - Call the function from main or other functions. 7. Types of operators in C: - Arithmetic (+, -, *, /, %) - Relational (==, !=, >, <, >=, <=) - Logical (&&, ||, !) - Bitwise (&, |, ^, ~, <<, >>) - Assignment (=, +=, -=, etc.) - Increment/Decrement (++ , --) - Conditional (?:) - Others (sizeof, comma operator) 8. Do-while loop to print from 10 to 1: ```c #include int main() { int i = 10; do { printf("%d\n", i); i--; } while (i >= 1); return 0; } ```