View Compilation Error

0_0_18178014_16958.c: In function 'main':
0_0_18178014_16958.c:17:25: error: 'm' undeclared (first use in this function)
  while(scanf("%d%d",&n,&m)!=EOF)
                         ^
0_0_18178014_16958.c:17:25: note: each undeclared identifier is reported only once for each function it appears in