Compilare: main.cpp: In function 'void dfs(int, int)': main.cpp:52:23: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(int i = 0 ; i < work.size() ; i++){ ~~^~~~~~~~~~~~~ main.cpp: In function 'int main()': main.cpp:68:9: warning: unused variable 'i' [-Wunused-variable] int i,j; ^ main.cpp:68:11: warning: unused variable 'j' [-Wunused-variable] int i,j; ^