molecules.cpp: In function 'int* find_subset(int, int, int*)':
molecules.cpp:47:10: warning: address of local variable 'res' returned [-Wreturn-local-addr]
47 | return res;
| ^~~
molecules.cpp:45:7: note: declared here
45 | int res[SZ(ans)];
| ^~~
molecules.h:1:9: warning: #pragma once in main file
1 | #pragma once
| ^~~~
molecules_c.h:1:9: warning: #pragma once in main file
1 | #pragma once
| ^~~~
/usr/bin/ld: /tmp/ccAgSBe8.o: in function `main':
grader.cpp:(.text.startup+0x0): multiple definition of `main'; /tmp/cc64BBBh.o:molecules.cpp:(.text.startup+0x0): first defined here
/usr/bin/ld: /tmp/ccAgSBe8.o: in function `main':
grader.cpp:(.text.startup+0x173): undefined reference to `find_subset(int, int, std::vector<int, std::allocator<int> >)'
collect2: error: ld returned 1 exit status