acop.cpp: In function 'void Back(int, int)': acop.cpp:46: warning: extended initializer lists only available with -std=c++0x or -std=gnu++0x acop.cpp:46: warning: extended initializer lists only available with -std=c++0x or -std=gnu++0x acop.cpp:47: warning: extended initializer lists only available with -std=c++0x or -std=gnu++0x acop.cpp:47: warning: extended initializer lists only available with -std=c++0x or -std=gnu++0x