View Compilation Error

0_0_37604336_9397.cpp: In function 'int main()':
0_0_37604336_9397.cpp:24:34: error: 'endl' was not declared in this scope
         std::cout << D[m] * a << endl;
                                  ^
0_0_37604336_9397.cpp:24:34: note: suggested alternative:
In file included from GCC4.9.2/x86_64-w64-mingw32/include/c++/iostream:39:0,
                 from 0_0_37604336_9397.cpp:1:
GCC4.9.2/x86_64-w64-mingw32/include/c++/ostream:564:5: note:   'std::endl'
     endl(basic_ostream<_CharT, _Traits>& __os)
     ^