View Compilation Error

0_0_26028002_10847.cpp: In function 'int main()':
0_0_26028002_10847.cpp:33:9: error: 'cin' was not declared in this scope
         cin >> x;
         ^
0_0_26028002_10847.cpp:34:9: error: 'cout' was not declared in this scope
         cout << fixed << setprecision(0);
         ^
0_0_26028002_10847.cpp:35:30: error: 'endl' was not declared in this scope
         cout << pow(2, x) << endl;
                              ^