Compilare: main.cpp: In function 'void dfs(int)': main.cpp:20:22: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(int i = 0; i < v[node].size(); i++) ~~^~~~~~~~~~~~~~~~ main.cpp: In function 'bool pairup(int)': main.cpp:35:22: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(int i = 0; i < v[node].size(); i++) ~~^~~~~~~~~~~~~~~~ main.cpp:44:23: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(int i = 0; i < v[node].size(); i++) ~~^~~~~~~~~~~~~~~~