Compilare: user.cpp: In function ‘void DFS(int, int)’: user.cpp:20:18: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(int i=0;i<Graph[node].size();i++) ~^~~~~~~~~~~~~~~~~~~ user.cpp: In function ‘void add_edge(int, int)’: user.cpp:33:19: warning: suggest parentheses around ‘&&’ within ‘||’ [-Wparentheses] else if(linked[x]&&sons[y]||(sons[y]&&sons[x])) ~~~~~~~~~^~~~~~~~~ user.cpp: In function ‘int main()’: user.cpp:67:28: warning: ignoring return value of ‘int fscanf(FILE*, const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] fscanf(IN,"%d%d",&N,&K); ^ user.cpp:70:49: warning: ignoring return value of ‘int fscanf(FILE*, const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] fscanf(IN,"%d%d%d",&A[i],&B[i],&cost[i]); ^