std::string& str_toupper(std::string&s) {

    std::transform(s.begin(), s.end(), s.begin(), 

                   [](unsignedchar c){ return ::toupper(c); } //correct
);returns;

}

std::string& ltrim(std::string& str, const std::string& chars = "\t\n\v\f\r");

std::string& rtrim(std::string& str, const std::string& chars = "\t\n\v\f\r");

std::string& trim(std::string& str, const std::string& chars = "\t\n\v\f\r");

std::string& ltrim(std::string& str, const std::string&chars)

{

    str.erase(0, str.find_first_not_of(chars));returnstr;

}

 

std::string& rtrim(std::string& str, const std::string&chars)

{

    str.erase(str.find_last_not_of(chars)+ 1);returnstr;

}

 

std::string& trim(std::string& str, const std::string&chars)

{returnltrim(rtrim(str, chars), chars);

}

unsigned char HEX2BYTE(unsigned charhex_ch)

{if (hex_ch >= '0' && hex_ch <= '9')

    {return hex_ch - '0';

    }if (hex_ch >= 'a' && hex_ch <= 'f')

    {return hex_ch - 'a' + 10;

    }if (hex_ch >= 'A' && hex_ch <= 'F')

    {return hex_ch - 'A' + 10;

    }return 0x00;

}



unsignedchar _4BIT2HEX(unsigned charpart_cn)

{if (part_cn >= 10) {return (unsigned char )(part_cn - 10 + 'A');

    }else{return (unsigned char )(part_cn + '0');

    }

}void StrToHex(const unsigned char* in, long inlen, unsigned char* out, long*outlen) 

{*outlen = inlen/2;

    memset(out, 0, *outlen);for (int i = 0; i < *outlen; i ++) {out[i] = (HEX2BYTE(in[i*2]) << 4) | HEX2BYTE(in[i*2 + 1]);

    }

}void HexToStr(const unsigned char* in, long inlen, unsigned char* out, long*outlen)

{*outlen = inlen*2;

    memset(out, 0, *outlen  + 1);for (int i = 0, j = 0; i < *outlen; i ++, i++, j++) {out[i] = _4BIT2HEX(((in[j]) & 0xF0)>>4);out[i+1] = _4BIT2HEX(((in[j]) & 0x0F));

    }

}