Compilare: user.cpp: In function ‘bool dfs(int)’: user.cpp:15:26: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(int u=0;u<g[v].size();++u) ^ user.cpp:24:26: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(int u=0;u<g[v].size();++u) ^ user.cpp: In function ‘int main()’: user.cpp:38:32: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("cuplaj.in","r",stdin); ^ user.cpp:39:34: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("cuplaj.out","w",stdout); ^ user.cpp:40:26: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%d%d%d",&n,&m,&e); ^ user.cpp:43:22: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%d%d",&a,&b); ^