C Language INTERVIEW QUESTION & ANSWERS
| 121. |
Difference between string constants and character constants? |
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The string constants are always enclosed in double quotes, while character constants are enclosed in apostrophes (single quotation marks).
A character constant has an equivalent integer value, whereas a single-character string constant does not have an equivalent integer value. |
| 122. |
What are built in functions? |
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The functions that are predefined and supplied along with the compiler are known as built in functions. They are also known as library functions. |
| 123. |
What is an abstract base class? |
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An abstract class is a class that is designed to be specifically used as a base class. An abstract class contains at least one pure virtual function. |
| 124. |
What is escape sequences? |
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An escape sequence is a set of characters, when taken together, represent one character which may have a special significance. Escape sequences help to format the outputs properly or create appropriate signals. |
| 125. |
What is the difference between formal and actual parameters? |
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The formal parameters are the parameters that are used to collect values or addresses from the calling function to a function being called, whereas the actual parameters are used for passing values or addresses from the calling function to a function being callcd. In call by value method, it is the value of actual parameter that is copied into the formal parameter of the function. In call by reference, it is the address of the actual parameter that is assigned to the formal parameter, i.e., both the formal and actual parameters have same address. If any change is made to the actual (or formal) parameter, the corresponding formal (or actual) parameter will be affected. |
