View Compilation Error

0_0_30504498_19525.cpp: In function 'int main()':
0_0_30504498_19525.cpp:22:9: error: 'cin' was not declared in this scope
         cin>>gcd>>lcm;
         ^
0_0_30504498_19525.cpp:47:13: error: 'cout' was not declared in this scope
             cout<<ans<<endl;
             ^
0_0_30504498_19525.cpp:47:24: error: 'endl' was not declared in this scope
             cout<<ans<<endl;
                        ^