View Compilation Error

0_0_35110501_6.cpp: In function 'int main()':
0_0_35110501_6.cpp:5:5: error: 'cin' was not declared in this scope
     cin>>t;
     ^
0_0_35110501_6.cpp:13:21: error: 'sort' was not declared in this scope
         sort(in,in+n);
                     ^
0_0_35110501_6.cpp:18:17: error: 'cout' was not declared in this scope
                 cout<<(i)*V<<" ";
                 ^
0_0_35110501_6.cpp:19:56: error: 'printf' was not declared in this scope
                 printf("%.2lf\n",i!=0?(sum-in[i])/i/V:0);
                                                        ^
0_0_35110501_6.cpp:22:17: error: 'cout' was not declared in this scope
                 cout<<(i+1)*V<<" ";
                 ^
0_0_35110501_6.cpp:23:47: error: 'printf' was not declared in this scope
                 printf("%.2lf\n",(sum)/(i+1)/V);
                                               ^