View Compilation Error

0_0_27201634_30119.cpp: In function 'int main()':
0_0_27201634_30119.cpp:6:24: error: 'scanf' was not declared in this scope
     scanf("%d %d",&a,&c);
                        ^
0_0_27201634_30119.cpp:7:20: error: 'printf' was not declared in this scope
     printf("%d",a+c);
                    ^