Compilare: user.cpp: In function ‘int main()’: user.cpp:52:34: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(int i=stpos;i<V.size();i+=2)fprintf(g,"%d %d ",V[i].first,V[i].second); ^ user.cpp:54:36: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(int i=stpos+1;i<V.size();i+=2)fprintf(g,"%d %d ",V[i].first,V[i].second); ^ user.cpp:58:36: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(int i=stpos+1;i<V.size();i+=2)fprintf(g,"%d %d ",V[i].first,V[i].second); ^ user.cpp:60:34: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(int i=stpos;i<V.size();i+=2)fprintf(g,"%d %d ",V[i].first,V[i].second); ^ user.cpp:34:30: warning: ignoring return value of ‘int fscanf(FILE*, const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] fscanf(f,"%d %d\n",&N,&M); ^ user.cpp:37:40: warning: ignoring return value of ‘int fscanf(FILE*, const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] fscanf(f,"%d %d %c\n",&x,&y,&c); ^