Compilare: main.cpp: In function 'void dfs(int)': main.cpp:17:21: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(int i = 0; i < l[x].size(); i++) ~~^~~~~~~~~~~~~ main.cpp: In function 'int main()': main.cpp:60:5: warning: this 'for' clause does not guard... [-Wmisleading-indentation] for(int i = 1; i <= n; i++) ^~~ main.cpp:62:9: note: ...this statement, but the latter is misleadingly indented as if it is guarded by the 'for' viz[nod] = 1; ^~~