View Compilation Error

0_0_15478206_6588.cpp: In function 'int main()':
0_0_15478206_6588.cpp:17:9: error: 'cout' was not declared in this scope
         cout<<sum+day<<endl;
         ^
0_0_15478206_6588.cpp:17:24: error: 'endl' was not declared in this scope
         cout<<sum+day<<endl;
                        ^