Compilare: main.cpp: In function 'void dfs(int)': main.cpp:23:18: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(int i=0;i<g[start_node].size();i++) ~^~~~~~~~~~~~~~~~~~~~~ main.cpp: In function 'int main()': main.cpp:57:31: warning: ignoring return value of 'int fscanf(FILE*, const char*, ...)', declared with attribute warn_unused_result [-Wunused-result] fscanf(in, "%d%d", &n, &m); ^ main.cpp:61:35: warning: ignoring return value of 'int fscanf(FILE*, const char*, ...)', declared with attribute warn_unused_result [-Wunused-result] fscanf(in, "%d%d", &x, &y); ^