View Compilation Error

0_0_13586319_15169.cpp: In function 'int main()':
0_0_13586319_15169.cpp:1:34: error: 'scanf' was not declared in this scope
 main(){int a;while(~scanf("%d",&a))printf("%d\n",a);}
                                  ^
0_0_13586319_15169.cpp:1:51: error: 'printf' was not declared in this scope
 main(){int a;while(~scanf("%d",&a))printf("%d\n",a);}
                                                   ^