Compilare: main.cpp: In function 'int ers(int, int)': main.cpp:15:15: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for (i=0;i<v[x].size();i++) ~^~~~~~~~~~~~ main.cpp:18:15: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for (i=0;i<v[y].size();i++) ~^~~~~~~~~~~~ main.cpp: In function 'int main()': main.cpp:28:25: warning: ignoring return value of 'int fscanf(FILE*, const char*, ...)', declared with attribute warn_unused_result [-Wunused-result] fscanf (fin,"%d",&t); ^ main.cpp:30:34: warning: ignoring return value of 'int fscanf(FILE*, const char*, ...)', declared with attribute warn_unused_result [-Wunused-result] fscanf (fin,"%d%d",&n,&m); ^ main.cpp:36:52: warning: ignoring return value of 'int fscanf(FILE*, const char*, ...)', declared with attribute warn_unused_result [-Wunused-result] fscanf (fin,"%d%d",&mch[i].x,&mch[i].y); ^