View Compilation Error

0_0_19215926_15390.cpp: In function 'int main()':
0_0_19215926_15390.cpp:46:29: error: 'scanf' was not declared in this scope
     while (~scanf ("%s", str) &&strcmp(str, "END"))
                             ^
0_0_19215926_15390.cpp:57:34: error: 'printf' was not declared in this scope
         printf ("%d %d\n", ri, rj);
                                  ^