/usr/bin/ld: /tmp/ccfVzj8K.o: in function `answer':
grader.c:(.text+0x0): multiple definition of `answer'; /tmp/cclsLb8M.o:cave.cpp:(.text+0x0): first defined here
/usr/bin/ld: /tmp/ccfVzj8K.o: in function `tryCombination':
grader.c:(.text+0x80): multiple definition of `tryCombination'; /tmp/cclsLb8M.o:cave.cpp:(.text+0x80): first defined here
/usr/bin/ld: /tmp/ccfVzj8K.o: in function `init()':
grader.c:(.text+0x110): multiple definition of `init()'; /tmp/cclsLb8M.o:cave.cpp:(.text+0x110): first defined here
/usr/bin/ld: /tmp/ccfVzj8K.o: in function `main':
grader.c:(.text.startup+0x0): multiple definition of `main'; /tmp/cclsLb8M.o:cave.cpp:(.text.startup+0x0): first defined here
collect2: error: ld returned 1 exit status