Compilare: main.cpp: In function 'int main()': main.cpp:57:34: warning: format '%d' expects argument of type 'int', but argument 3 has type 'std::vector<std::vector<int> >::size_type {aka long unsigned int}' [-Wformat=] fprintf(g,"%d\n",compo.size()); ^ main.cpp:50:28: warning: ignoring return value of 'int fscanf(FILE*, const char*, ...)', declared with attribute warn_unused_result [-Wunused-result] fscanf(f,"%d %d",&N,&M); ^ main.cpp:53:32: warning: ignoring return value of 'int fscanf(FILE*, const char*, ...)', declared with attribute warn_unused_result [-Wunused-result] fscanf(f,"%d %d",&x,&y); ^