Compilare: user.cpp: In function ‘void dfs(int, int)’: user.cpp:17:34: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(int i = 0;i<graf[x].size();i++) ^ user.cpp:18:11: warning: suggest explicit braces to avoid ambiguous ‘else’ [-Wparentheses] if(!viz[ graf[x][i] ]) ^