View Compilation Error

0_0_18116018_30273.cpp: In function 'int main()':
0_0_18116018_30273.cpp:54:4: error: 'cin' was not declared in this scope
    cin>>k;
    ^
0_0_18116018_30273.cpp:55:4: error: 'cout' was not declared in this scope
    cout<<dec(k,1,N,1)<<endl;
    ^
0_0_18116018_30273.cpp:55:24: error: 'endl' was not declared in this scope
    cout<<dec(k,1,N,1)<<endl;
                        ^