Compilare: main.cpp: In function 'void MST()': main.cpp:73:26: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(int k = 0; k < graph.size(); k++){ ~~^~~~~~~~~~~~~~ main.cpp: In function 'int main()': main.cpp:104:12: warning: unused variable 'to' [-Wunused-variable] int v, to, from; ^~ main.cpp:104:16: warning: unused variable 'from' [-Wunused-variable] int v, to, from; ^~~~