Compilare: main.cpp: In function 'void dfs(int)': main.cpp:13:18: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare] 13 | for(int i=0;i<v[a].size();i++) | ~^~~~~~~~~~~~ main.cpp: In function 'int main()': main.cpp:43:8: warning: 'start' may be used uninitialized [-Wmaybe-uninitialized] 43 | dfs(start); | ~~~^~~~~~~ main.cpp:34:9: note: 'start' was declared here 34 | int start; | ^~~~~