View Compilation Error

In file included from 0_0_20331517_26838.cpp:1:0:
0_0_20331517_26838.cpp: In function 'int main()':
0_0_20331517_26838.cpp:7:18: error: ISO C++ forbids comparison between pointer and integer [-fpermissive]
  while (gets(a)!=EOF)
                  ^