View Compilation Error

0_0_17597408_8942.cpp: In function 'int main()':
0_0_17597408_8942.cpp:4:34: error: 'scanf' was not declared in this scope
    while(~scanf("%d%d%d",&n,&u,&d)&&n)
                                  ^
0_0_17597408_8942.cpp:10:25: error: 'printf' was not declared in this scope
        printf("%d\n",sum);
                         ^