I have work on Weight Sensor project with HX711. When i upload the code to MEGA board it's shows this error..
libraries\HX711-master\HX711.cpp.o (symbol from plugin): In function `HX711::~HX711()':
(.text+0x0): multiple definition of `HX711::~HX711()'
sketch\HX711.cpp.o (symbol from plugin):(.text+0x0): first defined here
libraries\HX711-master\HX711.cpp.o (symbol from plugin): In function `HX711::~HX711()':
(.text+0x0): multiple definition of `HX711::~HX711()'
sketch\HX711.cpp.o (symbol from plugin):(.text+0x0): first defined here
libraries\HX711-master\HX711.cpp.o (symbol from plugin): In function `HX711::~HX711()':
(.text+0x0): multiple definition of `HX711::~HX711()'
sketch\HX711.cpp.o (symbol from plugin):(.text+0x0): first defined here
libraries\HX711-master\HX711.cpp.o (symbol from plugin): In function `HX711::~HX711()':
(.text+0x0): multiple definition of `HX711::is_ready()'
sketch\HX711.cpp.o (symbol from plugin):(.text+0x0): first defined here
libraries\HX711-master\HX711.cpp.o (symbol from plugin): In function `HX711::~HX711()':
(.text+0x0): multiple definition of `HX711::read()'
sketch\HX711.cpp.o (symbol from plugin):(.text+0x0): first defined here
libraries\HX711-master\HX711.cpp.o (symbol from plugin): In function `HX711::~HX711()':
(.text+0x0): multiple definition of `HX711::set_gain(unsigned char)'
sketch\HX711.cpp.o (symbol from plugin):(.text+0x0): first defined here
libraries\HX711-master\HX711.cpp.o (symbol from plugin): In function `HX711::~HX711()':
(.text+0x0): multiple definition of `HX711::HX711(unsigned char, unsigned char, unsigned char)'
sketch\HX711.cpp.o (symbol from plugin):(.text+0x0): first defined here
libraries\HX711-master\HX711.cpp.o (symbol from plugin): In function `HX711::~HX711()':
(.text+0x0): multiple definition of `HX711::HX711(unsigned char, unsigned char, unsigned char)'
sketch\HX711.cpp.o (symbol from plugin):(.text+0x0): first defined here
libraries\HX711-master\HX711.cpp.o (symbol from plugin): In function `HX711::~HX711()':
(.text+0x0): multiple definition of `HX711::read_average(unsigned char)'
sketch\HX711.cpp.o (symbol from plugin):(.text+0x0): first defined here
libraries\HX711-master\HX711.cpp.o (symbol from plugin): In function `HX711::~HX711()':
(.text+0x0): multiple definition of `HX711::get_value(unsigned char)'
sketch\HX711.cpp.o (symbol from plugin):(.text+0x0): first defined here
libraries\HX711-master\HX711.cpp.o (symbol from plugin): In function `HX711::~HX711()':
(.text+0x0): multiple definition of `HX711::get_units(unsigned char)'
sketch\HX711.cpp.o (symbol from plugin):(.text+0x0): first defined here
libraries\HX711-master\HX711.cpp.o (symbol from plugin): In function `HX711::~HX711()':
(.text+0x0): multiple definition of `HX711::tare(unsigned char)'
sketch\HX711.cpp.o (symbol from plugin):(.text+0x0): first defined here
libraries\HX711-master\HX711.cpp.o (symbol from plugin): In function `HX711::~HX711()':
(.text+0x0): multiple definition of `HX711::set_scale(float)'
sketch\HX711.cpp.o (symbol from plugin):(.text+0x0): first defined here
libraries\HX711-master\HX711.cpp.o (symbol from plugin): In function `HX711::~HX711()':
(.text+0x0): multiple definition of `HX711::get_scale()'
sketch\HX711.cpp.o (symbol from plugin):(.text+0x0): first defined here
libraries\HX711-master\HX711.cpp.o (symbol from plugin): In function `HX711::~HX711()':
(.text+0x0): multiple definition of `HX711::set_offset(long)'
sketch\HX711.cpp.o (symbol from plugin):(.text+0x0): first defined here
libraries\HX711-master\HX711.cpp.o (symbol from plugin): In function `HX711::~HX711()':
(.text+0x0): multiple definition of `HX711::get_offset()'
sketch\HX711.cpp.o (symbol from plugin):(.text+0x0): first defined here
libraries\HX711-master\HX711.cpp.o (symbol from plugin): In function `HX711::~HX711()':
(.text+0x0): multiple definition of `HX711::power_down()'
sketch\HX711.cpp.o (symbol from plugin):(.text+0x0): first defined here
libraries\HX711-master\HX711.cpp.o (symbol from plugin): In function `HX711::~HX711()':
(.text+0x0): multiple definition of `HX711::power_up()'
sketch\HX711.cpp.o (symbol from plugin):(.text+0x0): first defined here
collect2.exe: error: ld returned 1 exit status
exit status 1
Error compiling for board Arduino/Genuino Uno.