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#include <iostream>

#include <cstdlib>

#include <cstring>

class CCRC32

{

public:

    CCRC32() { initialize(); }

    unsigned long FullCRC(const unsigned char *sData, unsigned long ulDataLength)

    {

        unsigned long ulCRC = 0xffffffff;

        PartialCRC(&ulCRC, sData, ulDataLength);

        return(ulCRC ^ 0xffffffff);

    }

    void PartialCRC(unsigned long *ulCRC, const unsigned char *sData, unsigned long ulDataLength)

    {

        while(ulDataLength--) {

            *ulCRC = (*ulCRC >> 8) ^ ulTable[(*ulCRC & 0xFF) ^ *sData++];

        }

    }

private:

    void initialize(void)

    {

        unsigned long ulPolynomial = 0x04C11DB7;

        memset(&ulTable, 0, sizeof(ulTable));

        for(int iCodes = 0; iCodes <= 0xFF; iCodes++) {

            ulTable[iCodes] = Reflect(iCodes, 8) << 24;

            for(int iPos = 0; iPos < 8; iPos++) {

                ulTable[iCodes] = ((ulTable[iCodes] << 1) & 0xffffffff)

                    ^ ((ulTable[iCodes] & (1 << 31)) ? ulPolynomial : 0);

            }

            ulTable[iCodes] = Reflect(ulTable[iCodes], 32);

        }

    }

    unsigned long Reflect(unsigned long ulReflect, const char cChar)

    {

        unsigned long ulValue = 0;

        // Swap bit 0 for bit 7, bit 1 For bit 6, etc....

        for(int iPos = 1; iPos < (cChar + 1); iPos++) {

            if(ulReflect & 1) {

                ulValue |= (1ul << (cChar - iPos));

            }

            ulReflect >>= 1;

        }

        return ulValue;

    }

    unsigned long ulTable[256]; // CRC lookup table array.

};

int main(int argc, char **argv)

{

    CCRC32 crc;

    char *name;

    if (argc < 2) {

        std::cerr << "usage: crc <string>\n";

        return 0;

    } else {

        name = argv[1];

    }

    std::cout << crc.FullCRC((unsigned char *)name, strlen(name)) << std::endl;

}