View Compilation Error

0_0_24567380_12234.cpp: In function 'int main()':
0_0_24567380_12234.cpp:5:26: error: 'scanf' was not declared in this scope
     for (; scanf("%d", &n), n; k = puts("")) {
                          ^
0_0_24567380_12234.cpp:5:43: error: 'puts' was not declared in this scope
     for (; scanf("%d", &n), n; k = puts("")) {
                                           ^
0_0_24567380_12234.cpp:6:22: error: 'itoa' was not declared in this scope
         itoa(n, s, 20);
                      ^
0_0_24567380_12234.cpp:9:35: error: 'printf' was not declared in this scope
             k = printf("2,000,000");
                                   ^
0_0_24567380_12234.cpp:17:44: error: 'printf' was not declared in this scope
             k = printf(k ? ",%03d" : "%d",n);
                                            ^