View Compilation Error

0_0_27201977_27609.c: In function 'main':
0_0_27201977_27609.c:6:32: error: 'EOF' undeclared (first use in this function)
     while(scanf("%d%d",&n,&m)!=EOF)
                                ^
0_0_27201977_27609.c:6:32: note: each undeclared identifier is reported only once for each function it appears in