Compilare: user.cpp: In function ‘void visit(int)’: user.cpp:69:41: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for (int i = 0; i < vNode->edges.size(); i++) { ^ user.cpp: In function ‘int main()’: user.cpp:93:37: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for (int i = 0; i < solution.size(); i++) { ^ user.cpp: In function ‘void readInput()’: user.cpp:28:32: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("ctc.in", "r", stdin); ^ user.cpp:29:34: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("ctc.out", "w", stdout); ^ user.cpp:30:25: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%d %d", &n, &m); ^ user.cpp:36:27: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%d %d", &a, &b); ^