View Compilation Error

0_0_16498142_2057.cpp: In function 'int main()':
0_0_16498142_2057.cpp:4:37: error: 'scanf' was not declared in this scope
     while(scanf("%c%c%c",&a,&b,&c,&d)!=EOF)
                                     ^
0_0_16498142_2057.cpp:4:40: error: 'EOF' was not declared in this scope
     while(scanf("%c%c%c",&a,&b,&c,&d)!=EOF)
                                        ^
0_0_16498142_2057.cpp:26:29: error: 'printf' was not declared in this scope
    printf("%c %c %c\n",a,b,c);
                             ^