View Compilation Error

0_0_19461500_22534.cpp: In function 'int main(int, char**)':
0_0_19461500_22534.cpp:8:21: error: 'scanf' was not declared in this scope
  scanf("%d %d",&a,&b);
                     ^
0_0_19461500_22534.cpp:9:17: error: 'printf' was not declared in this scope
  printf("%d",a+b);
                 ^