/usr/bin/ld: /tmp/cct8thWU.o: in function `Add(int, int)':
arithmetics.cpp:(.text+0x0): multiple definition of `Add(int, int)'; /tmp/ccQuZ2EV.o:chessrush.cpp:(.text+0x0): first defined here
/usr/bin/ld: /tmp/cct8thWU.o: in function `Sub(int, int)':
arithmetics.cpp:(.text+0x80): multiple definition of `Sub(int, int)'; /tmp/ccQuZ2EV.o:chessrush.cpp:(.text+0x80): first defined here
/usr/bin/ld: /tmp/cct8thWU.o: in function `Mul(int, int)':
arithmetics.cpp:(.text+0x100): multiple definition of `Mul(int, int)'; /tmp/ccQuZ2EV.o:chessrush.cpp:(.text+0x100): first defined here
/usr/bin/ld: /tmp/cct8thWU.o: in function `modpow(int, int, int)':
arithmetics.cpp:(.text+0x190): multiple definition of `modpow(int, int, int)'; /tmp/ccQuZ2EV.o:chessrush.cpp:(.text+0x190): first defined here
/usr/bin/ld: /tmp/cct8thWU.o: in function `modinv(int, int)':
arithmetics.cpp:(.text+0x1f0): multiple definition of `modinv(int, int)'; /tmp/ccQuZ2EV.o:chessrush.cpp:(.text+0x1f0): first defined here
/usr/bin/ld: /tmp/cct8thWU.o: in function `Div(int, int)':
arithmetics.cpp:(.text+0x290): multiple definition of `Div(int, int)'; /tmp/ccQuZ2EV.o:chessrush.cpp:(.text+0x290): first defined here
collect2: error: ld returned 1 exit status