View Compilation Error

0_0_35360449_15175.cpp: In function 'int main()':
0_0_35360449_15175.cpp:8:3: error: 'cout' was not declared in this scope
   cout<<sum<<endl<<endl;
   ^
0_0_35360449_15175.cpp:8:14: error: 'endl' was not declared in this scope
   cout<<sum<<endl<<endl;
              ^