Compilare: main.cpp: In function 'void dfs(int)': main.cpp:19:15: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for (i=0;i<l[s].size();i++) { ~^~~~~~~~~~~~ main.cpp: In function 'int main()': main.cpp:53:19: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for (j=0;j<l[f[i]].size();j++) { ~^~~~~~~~~~~~~~~ main.cpp:71:22: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(j=0;j<g[f[i]].size();j++) { ~^~~~~~~~~~~~~~~