View Compilation Error

0_0_22200907_23596.cpp: In function 'int main()':
0_0_22200907_23596.cpp:7:14: error: 'scanf' was not declared in this scope
 scanf("%d",&a);
              ^
0_0_22200907_23596.cpp:9:16: error: 'printf' was not declared in this scope
 printf("%d\n",b);
                ^