Compilare: user.cpp: In function ‘int Try(int)’: user.cpp:17:30: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for (int i=0;i<a[x].size();i++) ^ user.cpp:25:30: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for (int i=0;i<a[x].size();i++) ^ user.cpp: In function ‘int main()’: user.cpp:49:36: warning: ignoring return value of ‘int fscanf(FILE*, const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] fscanf(f,"%d%d%d",&n,&m,&e); ^ user.cpp:60:35: warning: ignoring return value of ‘int fscanf(FILE*, const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] fscanf(f,"%d%d",&x,&y); ^