View Compilation Error

1_798_656_1495.cpp: In function 'int main()':
1_798_656_1495.cpp:8:26: error: 'scanf' was not declared in this scope
     while (scanf("%d", &n) == 1) {  
                          ^
1_798_656_1495.cpp:17:25: error: 'printf' was not declared in this scope
         printf("%d\n", h);  
                         ^