regat.cpp: In function 'void dfs(int)': regat.cpp:39: warning: comparison between signed and unsigned integer expressions regat.cpp: In function 'int main()': regat.cpp:213: warning: extended initializer lists only available with -std=c++0x or -std=gnu++0x regat.cpp:213: warning: extended initializer lists only available with -std=c++0x or -std=gnu++0x regat.cpp:215: warning: extended initializer lists only available with -std=c++0x or -std=gnu++0x regat.cpp:215: warning: extended initializer lists only available with -std=c++0x or -std=gnu++0x regat.cpp:251: warning: comparison between signed and unsigned integer expressions regat.cpp:309: warning: comparison between signed and unsigned integer expressions