View Compilation Error

0_0_20675424_14414.cpp: In function 'int main()':
0_0_20675424_14414.cpp:29:40: error: 'd' was not declared in this scope
         for (i=1;i<12;i++) ans=max(ans,d[end][i]);
                                        ^
0_0_20675424_14414.cpp:30:9: error: 'cout' was not declared in this scope
         cout<<ans<<endl; 
         ^
0_0_20675424_14414.cpp:30:20: error: 'endl' was not declared in this scope
         cout<<ans<<endl; 
                    ^