Compilare: main.cpp: In function 'void dfs_down(int, int)': main.cpp:21:15: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for (i=0;i<v[nod].size();i++){ ~^~~~~~~~~~~~~~ main.cpp: In function 'void dfs_up(int, int)': main.cpp:46:19: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for (i=0;i<v[tt].size();i++){ ~^~~~~~~~~~~~~ main.cpp:60:15: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for (i=0;i<v[nod].size();i++){ ~^~~~~~~~~~~~~~ main.cpp: In function 'int main()': main.cpp:73:25: warning: ignoring return value of 'int fscanf(FILE*, const char*, ...)', declared with attribute warn_unused_result [-Wunused-result] fscanf (fin,"%d",&n); ^ main.cpp:75:48: 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); ^