View Compilation Error

0_0_15296456_29869.cpp: In function 'int main()':
0_0_15296456_29869.cpp:5:42: error: 'scanf' was not declared in this scope
     while(scanf("%d %d %d %d",&a,&b,&s,&t) && (a||b||s||t)) {
                                          ^
0_0_15296456_29869.cpp:15:28: error: 'printf' was not declared in this scope
         printf("%d\n",count);
                            ^