View Compilation Error

0_0_34212194_23991.cpp: In function 'int main()':
0_0_34212194_23991.cpp:4:24: error: 'scanf' was not declared in this scope
      scanf("%d%d",&a,&b);
                        ^
0_0_34212194_23991.cpp:6:21: error: 'printf' was not declared in this scope
      printf("%d\n",c);
                     ^