honest.cpp: In function 'void dfs(int)': honest.cpp:21: warning: comparison between signed and unsigned integer expressions honest.cpp: In function 'void dfs2(int)': honest.cpp:32: warning: comparison between signed and unsigned integer expressions honest.cpp: In function 'int main()': honest.cpp:50: warning: extended initializer lists only available with -std=c++0x or -std=gnu++0x honest.cpp:50: warning: extended initializer lists only available with -std=c++0x or -std=gnu++0x