View Compilation Error

0_0_19215591_4727.cpp: In function 'int main()':
0_0_19215591_4727.cpp:32:24: error: 'scanf' was not declared in this scope
     while(scanf("%d",&n)!=EOF)
                        ^
0_0_19215591_4727.cpp:32:27: error: 'EOF' was not declared in this scope
     while(scanf("%d",&n)!=EOF)
                           ^
0_0_19215591_4727.cpp:46:21: error: 'getchar' was not declared in this scope
             getchar();
                     ^
0_0_19215591_4727.cpp:48:44: error: 'printf' was not declared in this scope
             if(c=='Q') printf("%I64d\n",ans);
                                            ^