Compilare: user.cpp: In function ‘void Read()’: user.cpp:22:10: warning: unused variable ‘ch’ [-Wunused-variable] char ch; ^ user.cpp: In function ‘void DFS(int)’: user.cpp:37:37: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(int i = 0; i < G[node].size(); i++) ^ user.cpp:36:9: warning: unused variable ‘cnt’ [-Wunused-variable] int cnt = 0; ^ user.cpp: In function ‘int main()’: user.cpp:68:35: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(int i = 0; i < B.size(); i++) ^ user.cpp:71:45: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(int j = 0; j < G[node].size(); j++) ^ user.cpp:90:36: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(int i = 0; i < B2.size(); i++) ^ user.cpp:94:36: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(int i = 0; i < B2.size(); i++) ^ user.cpp: In function ‘void Read()’: user.cpp:19:22: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%d\n", &N); ^ user.cpp:21:25: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%s", Val + 1); ^ user.cpp:27:30: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%d%d", &x, &y); ^ user.cpp: In function ‘int main()’: user.cpp:48:37: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("parb.out", "w", stdout); ^ user.cpp:49:35: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("parb.in", "r", stdin); ^