Logic & Programming GFACT Practice Questions (Page 6)

Questions 26–30

1. 26application · medium

   A C program allocates memory for a string using malloc() and later calls free() on the pointer. After freeing, the programmer accidentally uses the pointer again. What is this type of error?

   • AMemory leak
   • BNull pointer dereference
   • CBuffer overflow
   • DUse-after-free
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2. 27expert · medium

   A C programmer needs to allocate memory for a dynamic array of structs. The programmer uses malloc() but forgets to multiply by the size of the struct. What is the most likely result?

   • AA syntax error
   • BA memory leak
   • CA buffer overflow when accessing elements beyond the allocated memory
   • DThe program runs correctly
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4. 28application · medium

   A security analyst is writing a script to filter network alerts. The script should trigger an alert only when both the source IP is in the internal range AND the destination port is 22. The analyst writes: `if (source_internal AND dest_port == 22): alert()`. During testing, the alert fires when the source is internal but the destination port is 443. What is the most likely cause?

   • AThe comparison `dest_port == 22` should have been `dest_port != 22`.
   • BThe AND operator was incorrectly implemented as OR in the code.
   • CThe dest_port variable was not initialized before the comparison.
   • DThe AND operator has higher precedence than the equality operator, causing the condition to evaluate incorrectly.
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5. 29foundation · easy

   Which of the following is a valid variable declaration and assignment in Python?

   • Aint x = 5;
   • Bx = 5
   • Cvar x = 5;
   • Dlet x = 5
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6. 30application · medium

   A developer is debugging a C program that crashes when it tries to free a pointer. The pointer was allocated with malloc() and has not been freed before. What is the most likely cause of the crash?

   • AThe pointer is NULL
   • BThe program did not include stdlib.h
   • CThe pointer was modified after allocation, so free() receives an invalid address
   • DThe program used calloc() instead of malloc()
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