View Compilation Error

0_0_37206372_13662.cpp: In function 'int main()':
0_0_37206372_13662.cpp:4:31: error: 'scanf' was not declared in this scope
     while(scanf("%d%d", &n, &m), n+m)
                               ^
0_0_37206372_13662.cpp:7:25: error: 'printf' was not declared in this scope
         printf("%d\n", n);
                         ^