C Programming Test to recruit the top C developers

The C Programming Assessment by Mercer | Mettl evaluates a developer's skills and knowledge in building a software program in C language. This Online C Coding Test assesses proficiencies in C programming basics, advanced topics, data structures, and hands-on programming. 

What is C programming language?

C is a general-purpose, procedural, high-level programming language that develops computer software and applications, system programming, games, and more. It was developed by Dennis M. Ritchie in 1972. It is a powerful and flexible language and is one of the most widely used programming languages known for its simplicity and efficiency.   

What is inside this C Coding Test?

This sixty-minutes test includes eighteen MCQs and two backend coding problems to be solved using the coding simulator. Designed by industry experts, the assessment evaluates skills on three levels - basic, intermediate and advanced. The test holistically assesses an applicant's knowledge and applied coding skills.

What skills does this C Programming Test cover? 

• Hands-on programming

This backend simulator-based test evaluates a candidate's applied coding skills in resolving debugging questions.   

• C programming basics   

This subskill evaluates proficiency in C - Arrays - Application, C - Basics - Application, C - Bitwise Operations - Application, C - Code Snippet - Application, C - Control Statements - Application, C - Functions - Application, C - Recursion - Application and C - Strings - Application.   

• Data structures   

This subskill evaluates data structures, such as linked list, stack, and queue proficiency.   

• Advanced topics   

This subskill evaluates proficiency in C - Pointers - Application and C - Structure and Union - Application.

What roles can you assess using the C Coding Test?

• C developer- The responsibilities of a C developer include developing kernel modules, embedded systems, and libraries for high-level languages, studying APIs of different environments, and applying C skills to create efficient and reliable modules.
• Junior C developer- The responsibilities of a junior C developer are like those of a C developer but at a junior level. They develop code that integrates into base operating systems, kernel modules, and embedded systems for other high-level languages.
• Backend developer- Backend developer responsibilities include creating, testing, maintaining, and debugging the entire back end of an application or system. C programming is a language that can develop high-performance systems and operating systems for backend programming.

Sample public questions for C Programming Test

1. What keyword transfers control from a function back to the calling function?   

The keyword 'return' transfers control from a function back to the calling function.   

2.  What are the types of linkages?   

The types of linkages are-    

• External Linkage: It refers to global, non-static variables and functions.   

• Internal Linkage: It relates to static variables and functions with file scope.  

• None Linkage: It means local variables. 

 

3. What is the difference between scanf and printf in C?   

printf is used for output (printing), while scanf is used for input (scanning) in C. printf displays data on the screen, and scanf reads data from the user.   

4. What is a variable in C?   

A variable refers to a named memory location that stores data. It has a data type (e.g., int, float) and a value.   

5. What is the difference between malloc and calloc?   

Malloc allocates memory; however, it does not initialize it. On the other hand, calloc allocates and initializes memory to zero.   

6. What is the purpose of the free function in C?   

The free function deallocates memory previously allocated with malloc, calloc, or realloc. It helps prevent memory leaks.   

7. What is the difference between an array and a pointer in C?   

An array refers to a fixed-size collection of elements. A pointer, on the other hand, refers to a variable that stores a memory address. Arrays have a fixed size, but pointers can point to different memory locations.   

8.  How do you pass arguments to a C function?   

One can pass arguments to a C function by including them within parentheses in the function’s declaration and definition.   

9.  Explain the difference between getc and fgetc in C.   

getc is a standard library macro, while fgetc is a standard library function. They both read a character from a file, but fgetc is more commonly used.   

10. Which bitwise operator is appropriate for checking whether a particular bit is on or off?   

“& operator” is appropriate for checking whether a particular bit is on or off.   

11. Explain the concept of a null-terminated string in C.   

A null-terminated string in C is a character array where the end of the string is marked by a null character ('\0'). It's used to represent and manipulate strings in C.   

12. What are the modes for opening a file in C using fopen?   

Common modes include "r" (read), "w" (write), "a" (append), "rb" (read binary), "wb" (write binary), etc.   

13. What are the basic data types in C?   

Basic data types in C include int, float, double, char, and void.   

14. What is the similarity between a structure, union and enumeration?   

The similarity between structure, union, and enumeration is that they define new data types. 

15. In which header file are input/output function prototypes and macros defined?   

stdio.h, "standard input/output header", is the C standard library header file consisting of constants, macro definitions, and declarations of functions and types for various standard input and output operations.