Compilation of string literals

Question

Why can two string literals separated by a space, tab or \"\\n\" be compiled without an error?

int main()
{
   char * a = \"aaaa\"  \"bbbb\";
} 

Answer 1

String literals placed side-by-side are concatenated at translation phase 6 (after the preprocessor). That is, "Hello," " world!" yields the (single) string "Hello, world!". If the two strings have the same encoding prefix (or neither has one), the resulting string will have the same encoding prefix (or no prefix).

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