foo.cpp: In function 'int main()':
foo.cpp:4:5: warning: 'auto' changes meaning in C++11; please remove it [-Wc++0x-compat]
     auto f=[](int a,int b){return a+b;};
     ^
foo.cpp:4:10: error: 'f' does not name a type
     auto f=[](int a,int b){return a+b;};
          ^
foo.cpp:7:16: error: 'f' was not declared in this scope
     cout<<f(a,b)<<endl;
                ^