Compilare: user.cpp: In function ‘void dfs1(int)’: user.cpp:16:30: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(int i=0; i<g[u].size(); ++i) if(!f[g[u][i]]) { ^ user.cpp: In function ‘void dfs2(int, int)’: user.cpp:30:30: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(int i=0; i<g[u].size(); ++i) if(!f[g[u][i]]) { ^ user.cpp:40:30: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(int i=0; i<g[u].size(); ++i) if(!f[g[u][i]]) { ^ user.cpp: In function ‘int main()’: user.cpp:49:38: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("razboi.in", "r", stdin); ^ user.cpp:50:39: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("razboi.out", "w", stdout); ^ user.cpp:53:22: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%d", &tsk); ^ user.cpp:55:24: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%d", &n); ^ user.cpp:61:40: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%d%d%d", &u, &v, &w); ^