In file included from /usr/include/c++/4.4/unordered_map:35, from diff.cpp:3: /usr/include/c++/4.4/c++0x_warning.h:31:2: error: #error This file requires compiler and library support for the upcoming ISO C++ standard, C++0x. This support is currently experimental, and must be enabled with the -std=c++0x or -std=gnu++0x compiler options. diff.cpp: In function 'int main()': diff.cpp:26: error: 'unordered_map' was not declared in this scope diff.cpp:26: error: expected primary-expression before 'int' diff.cpp:26: error: expected ';' before 'int' diff.cpp:41: error: 'rasp' was not declared in this scope diff.cpp:49: error: 'rasp' was not declared in this scope diff.cpp:65: error: 'unordered_map' was not declared in this scope diff.cpp:65: error: expected primary-expression before 'int' diff.cpp:65: error: expected ';' before 'int' diff.cpp:66: error: 'exista' was not declared in this scope