View Compilation Error

0_0_27164465_26542.c: In function 'main':
0_0_27164465_26542.c:4:28: error: 'EOF' undeclared (first use in this function)
     while(scanf("%lf",&a)!=EOF)
                            ^
0_0_27164465_26542.c:4:28: note: each undeclared identifier is reported only once for each function it appears in