View Compilation Error

0_0_13310023_3259.cpp: In function 'void work()':
0_0_13310023_3259.cpp:69:5: error: 'cout' was not declared in this scope
     cout << f[(1 << n) - 1] % (1000000007) << endl;
     ^
0_0_13310023_3259.cpp:69:47: error: 'endl' was not declared in this scope
     cout << f[(1 << n) - 1] % (1000000007) << endl;
                                               ^