Compilare: user.cpp: In function ‘void print(int)’: user.cpp:18:25: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for (uint32_t i = 0; i < pos; ++i) ~~^~~~~ user.cpp: In function ‘bool backtrack(int, int)’: user.cpp:44:9: warning: unused variable ‘res’ [-Wunused-variable] bool res = backtrack(pos + 1, n); ^~~ user.cpp: At global scope: user.cpp:9:13: warning: ‘test’ defined but not used [-Wunused-variable] static bool test = false; ^~~~