Compilare: main.cpp: In function 'void dfs(int)': main.cpp:10:19: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for (int b=0;b<v[a].size();b++) { ~^~~~~~~~~~~~ main.cpp: In function 'int main()': main.cpp:22:32: 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:24:36: warning: ignoring return value of 'int fscanf(FILE*, const char*, ...)', declared with attribute warn_unused_result [-Wunused-result] fscanf(fin, "%d%d" ,&a ,&b); ^