Compilare: user.cpp: In function ‘void dfs(int)’: user.cpp:17:38: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for (int i = 0; i < G[node].size(); i++) ^ user.cpp: In function ‘int main()’: user.cpp:79:51: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for (int j = 0; j < G[v].size(); j++) ^ user.cpp:90:51: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for (int j = 0; j < G[0].size(); j++) ^ user.cpp:111:34: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for (int i = 0; i < Sol.size(); i++) ^ user.cpp:114:41: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for (int j = 0; j < Sol[i].size(); j++) ^ user.cpp: In function ‘void advance()’: user.cpp:36:33: warning: ignoring return value of ‘size_t fread(void*, size_t, size_t, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] fread(buff,1,SIZE,stdin); ^ user.cpp: In function ‘int main()’: user.cpp:51:35: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("johnie.in","r",stdin); ^ user.cpp:52:37: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("johnie.out","w",stdout); ^