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c++ - Why can you add an integer to a string literal?

I was messing around and noticed something strange. You can actually do "a" + 2 and the program compiles fine, but doesn't output anything. However "a" + 32 says array subscript is above array bounds.

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"a" is actually a const char[], but it can be converted without a cast to a const char* or to a char* and when you do math on pointers it works like array subscript syntax. So you're creating a new pointer which is farther along in the string. This reference on pointer arithmetic might be useful. If you do get a char* reference to the literal, it still is undefined to modify it (from experience it might crash if in read-only page, or might change all references where it is used).


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