View Compilation Error

0_0_25229001_9673.c: In function 'main':
0_0_25229001_9673.c:5:30: error: 'EOF' undeclared (first use in this function)
  while(scanf("%d %d",&a,&b)!=EOF)
                              ^
0_0_25229001_9673.c:5:30: note: each undeclared identifier is reported only once for each function it appears in