Compilare: main.cpp: In function 'void prim()': main.cpp:5:41: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] #define FOR(i, a, b) for(int i = (a); i <= (b); ++i) ^ main.cpp:73:2: note: in expansion of macro 'FOR' FOR(i, 0, g[1].size() - 1) ^~~ main.cpp:5:41: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] #define FOR(i, a, b) for(int i = (a); i <= (b); ++i) ^ main.cpp:90:3: note: in expansion of macro 'FOR' FOR(j, 0, g[node].size() - 1) ^~~ main.cpp: In function 'void solve()': main.cpp:141:24: warning: 'y' may be used uninitialized in this function [-Wmaybe-uninitialized] removeFromTree(x, y); ^ main.cpp:141:24: warning: 'x' may be used uninitialized in this function [-Wmaybe-uninitialized]