View Compilation Error

0_0_22355722_24129.cpp: In function 'int main()':
0_0_22355722_24129.cpp:4:42: error: 'scanf' was not declared in this scope
  while(scanf("%d/%d/%d",&year,&month,&day)!=EOF)
                                          ^
0_0_22355722_24129.cpp:4:45: error: 'EOF' was not declared in this scope
  while(scanf("%d/%d/%d",&year,&month,&day)!=EOF)
                                             ^
0_0_22355722_24129.cpp:29:19: error: 'printf' was not declared in this scope
  printf("%d\n",ans); 
                   ^