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Similarly, comparing pointers using the relational operators <, <=, >=, and > gives the positions of the pointers relative to each other. Subtracting or comparing pointers that do not refer to the same array results in undefined behavior. (See undefined behavior 46 50 of Appendix J.)
Comparing pointers using the equality operators == and != has well-defined semantics regardless of whether or not either of the pointers is null, points into the same object, one past the last element of an array object, or function.
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