View Compilation Error

0_0_32598417_20937.cpp: In function 'int main()':
0_0_32598417_20937.cpp:4:36: error: 'scanf' was not declared in this scope
  while (scanf(" %c%c%c", &a, &b, &c) != EOF) {
                                    ^
0_0_32598417_20937.cpp:4:41: error: 'EOF' was not declared in this scope
  while (scanf(" %c%c%c", &a, &b, &c) != EOF) {
                                         ^
0_0_32598417_20937.cpp:21:31: error: 'printf' was not declared in this scope
   printf("%c %c %c\n", a, b, c);
                               ^