Govt. Exams
Entrance Exams
Variables declared inside a block (including function blocks) have block scope and are accessible only within that block.
unsigned char is 1 byte (8 bits) without sign bit, giving range 0 to 2^8-1 = 0 to 255.
In C, floating-point constants like 3.14 are treated as double by default. To specify float, you need to use 3.14f suffix.
On 32-bit systems, int is typically 4 bytes (32 bits). However, the exact size is implementation-defined per C standard.
Variable names cannot start with a digit in C. Valid names must begin with a letter (a-z, A-Z) or underscore (_).
In standard C on 64-bit systems, double occupies 8 bytes and can store values with approximately 15-17 significant digits.
The const keyword makes a variable read-only after initialization. Its value cannot be modified during program execution.
A signed char occupies 1 byte (8 bits). With sign bit, it ranges from -128 to 127 (2^7 to 2^7-1).
Standard C guarantees short int is at least 16 bits (2 bytes). Most systems use exactly 16 bits.
Derived data types are created from fundamental types. Arrays, pointers, structures, and unions are derived types.
