Compilare: main.cpp: In function 'void solve1()': main.cpp:78:22: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(int i = 0; i < edges.size(); i++) { ~~^~~~~~~~~~~~~~ main.cpp: In function 'void solve2()': main.cpp:88:22: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(int i = 0; i < edges.size(); i++) { ~~^~~~~~~~~~~~~~ main.cpp: In function 'void solve3()': main.cpp:98:22: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(int i = 0; i < edges.size(); i++) { ~~^~~~~~~~~~~~~~