Compilare: main.cpp: In function 'void solve(int*)': main.cpp:34:20: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for (int i=0; i<edge[node].size(); i++){ ~^~~~~~~~~~~~~~~~~~ main.cpp: In function 'int main()': main.cpp:60:13: warning: unused variable 'x1' [-Wunused-variable] int x1, x2, y1, y2; ^~ main.cpp:60:17: warning: unused variable 'x2' [-Wunused-variable] int x1, x2, y1, y2; ^~ main.cpp:60:21: warning: unused variable 'y1' [-Wunused-variable] int x1, x2, y1, y2; ^~ main.cpp:60:25: warning: unused variable 'y2' [-Wunused-variable] int x1, x2, y1, y2; ^~