Integer and long integer literals are described by the following lexical definitions:
Although both lower case `l' and upper case `L' are allowed as suffix for long integers, it is strongly recommended to always use `L', since the letter `l' looks too much like the digit `1'.
Plain integer decimal literals must be at most 2147483647 (i.e., the largest positive integer, using 32-bit arithmetic). Plain octal and hexadecimal literals may be as large as 4294967295, but values larger than 2147483647 are converted to a negative value by subtracting 4294967296. There is no limit for long integer literals apart from what can be stored in available memory.
Some examples of plain and long integer literals:
7 2147483647 0177 0x80000000 3L 79228162514264337593543950336L 0377L 0x100000000L
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