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Char data type in C / C ++

I am trying to call a C ++ DLL in Java. Its main C ++ file has the following lines:

    #define a '102001'
    #define b '102002'
    #define c '202001'
    #define d '202002'

What data type is for a, b, c and d? are they char or char an array? and what is the corresponding data type in Java that I have to convert to?

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2 answers

As noted in Mysticial , these are multichannel literals . Their type is implementation dependent, but it is probably Java longbecause they use 48 bits.

In Java, you need to convert them to longmanually:

static long toMulticharConst(String s) {
    long res = 0;
    for (char c : s.toCharArray()) {
        res <<= 8;
        res |= ((long)c) & 0xFF;
    }
    return res;
}

final long a = toMulticharConst("102001");
final long b = toMulticharConst("102002");
final long c = toMulticharConst("202001");
final long d = toMulticharConst("202002");
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I can try to answer the first two questions. Not familiar with java, I have to leave the last question to others.

C. , , , , (, ASCII "a" , 97).

, , , , 0.

, , C , , , abc "abc" . , "abc" , , 4 (a, b, c \0), "abc" . C " , - a, b c.

1.4 "C "

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