Compilare: user.cpp: In function ‘void dfs(int, int)’: user.cpp:21:38: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for (int i = 0 ; i < g[act].size() ; ++i) ^ user.cpp: In function ‘void makeC(int, int, int&)’: user.cpp:37:38: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for (int i = 0 ; i < g[act].size() ; ++i) ^ user.cpp: In function ‘int main()’: user.cpp:95:36: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("hacker2.in" , "r" , stdin); ^ user.cpp:96:38: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("hacker2.out" , "w" , stdout); ^ user.cpp:98:19: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%d\n" , &n); ^ user.cpp:99:19: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%d\n" , &q); ^ user.cpp:103:21: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%d" , &a); ^ user.cpp:104:21: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%d" , &b); ^ user.cpp:105:21: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%d" , &c); ^ user.cpp:127:21: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%d" , &a); ^ user.cpp:128:21: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%d" , &b); ^