Compilare: main.cpp: In function 'void dfs(int, int, int)': main.cpp:18:16: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(int i=0;i<ln[l].size();i++){ ~^~~~~~~~~~~~~ main.cpp:25:16: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(int i=0;i<cl[c].size();i++){ ~^~~~~~~~~~~~~