Compilare: user.cpp: In function ‘int main()’: user.cpp:106:40: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(j=0;j<graph[node].size();j++) ^ user.cpp:112:33: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(j=0;j<graph[x].size();j++){ ^ user.cpp:86:34: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("atac2.in","r",stdin); ^ user.cpp:87:36: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("atac2.out","w",stdout); ^ user.cpp:89:34: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%d%d%d%d",&n,&m,&u,&x); ^ user.cpp:91:29: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%d",&unit[i]); ^ user.cpp:93:28: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%d%d",&a,&b); ^