Consider the following C statements:
char *str1 = "Hello; /* Statement S1 */
char *str2 = "Hello;"; /* Statement S2 */
int *str3 = "Hello"; /* Statement S3 */
Which of the following options is/are correct?
Consider the following C statements:
char *str1 = "Hello; /* Statement S1 */
char *str2 = "Hello;"; /* Statement S2 */
int *str3 = "Hello"; /* Statement S3 */
Which of the following options is/are correct?
Show Hint
- S1 and S2 have syntactic errors
- S2 has a lexical error and S3 has a syntactic error
- S1 has a lexical error and S3 has a semantic error
- S1 has a syntactic error and S3 has a semantic error
The Correct Option is C
Solution and Explanation
Step 1: Examine Statement S1: char *str1 = 'Hello; The string literal is opened with a double quote but never closed before the line ends. An unterminated string literal is a lexical error because the scanner cannot recognize a complete string-literal token.
Step 2: Examine Statement S2: char *str2 = 'Hello;'; Here the string literal is 'Hello;' (the semicolon inside the quotes is just a character of the string), properly closed with a quote, followed by the real terminating semicolon. This line has no lexical or syntactic problem; it simply initializes str2 with the text Hello;.
Step 3: Examine Statement S3: int *str3 = 'Hello'; The literal 'Hello' is a valid, well-formed string constant, so lexically and syntactically the statement is fine. However, a string literal has type char *, and it is being assigned to a variable of type int *. This type mismatch is a semantic error (most compilers issue a warning for the incompatible pointer type, and strict compilers reject it).
Step 4: Putting these together: S1 has a lexical error and S3 has a semantic error, which is exactly option C.
\[ \boxed{\text{Option C is correct}} \]
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