View Compilation Error

0_0_14721857_7643.cpp: In function 'int main()':
0_0_14721857_7643.cpp:7:9: error: 'cout' was not declared in this scope
         cout<<a+b<<endl;
         ^
0_0_14721857_7643.cpp:7:20: error: 'endl' was not declared in this scope
         cout<<a+b<<endl;
                    ^