Câu hỏi phỏng vấn về C (tt)
6) What are the features of the C language?
The main features of C language are given below:
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Simple: C is a simple language because it follows the structured approach, i.e., a program is broken into parts
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Portable: C is highly portable means that once the program is written can be run on any machine with little or no modifications.
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Mid Level: C is a mid-level programming language as it combines the low- level language with the features of the high-level language.
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Structured: C is a structured language as the C program is broken into parts.
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Fast Speed: C language is very fast as it uses a powerful set of data types and operators.
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Memory Management: C provides an inbuilt memory function that saves the memory and improves the efficiency of our program.
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Extensible: C is an extensible language as it can adopt new features in the future.
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7) What is the use of printf() and scanf() functions?
printf(): The printf() function is used to print the integer, character, float and string values on to the screen.
Following are the format specifier:
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%d: It is a format specifier used to print an integer value.
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%s: It is a format specifier used to print a string.
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%c: It is a format specifier used to display a character value.
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%f: It is a format specifier used to display a floating point value.
scanf(): The scanf() function is used to take input from the user.
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8) What is the difference between the local variable and global variable in C?
Following are the differences between a local variable and global variable:
Basis for comparison |
Local variable |
Global variable |
Declaration |
A variable which is declared inside function or block is known as a local variable. |
A variable which is declared outside function or block is known as a global variable. |
Scope |
The scope of a variable is available within a function in which they are declared. |
The scope of a variable is available throughout the program. |
Access |
Variables can be accessed only by those statements inside a function in which they are declared. |
Any statement in the entire program can access variables. |
Life |
Life of a variable is created when the function block is entered and destroyed on its exit. |
Life of a variable exists until the program is executing. |
Storage |
Variables are stored in a stack unless specified. |
The compiler decides the storage location of a variable. |
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9) What is the use of a static variable in C?
Following are the uses of a static variable:
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A variable which is declared as static is known as a static variable. The static variable retains its value between multiple function calls.
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Static variables are used because the scope of the static variable is available in the entire program. So, we can access a static variable anywhere in the program.
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The static variable is initially initialized to zero. If we update the value of a variable, then the updated value is assigned.
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The static variable is used as a common value which is shared by all the methods.
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The static variable is initialized only once in the memory heap to reduce the memory usage.
More details.
10) What is the use of the function in C?
Uses of C function are:
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C functions are used to avoid the rewriting the same code again and again in our program.
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C functions can be called any number of times from any place of our program.
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When a program is divided into functions, then any part of our program can easily be tracked.
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C functions provide the reusability concept, i.e., it breaks the big task into smaller tasks so that it makes the C program more understandable.
Sưu Tầm: Nguyễn Thị Bảo Trang