View Compilation Error

0_0_33107354_432.cpp: In function 'void dfs2(int, int)':
0_0_33107354_432.cpp:136:12: error: reference to 'tm' is ambiguous
  bh[x] = ++tm;
            ^
0_0_33107354_432.cpp:9:5: note: candidates are: int tm
 int tm;
     ^
In file included from GCC4.9.2/x86_64-w64-mingw32/include/c++/ctime:42:0,
                 from GCC4.9.2/x86_64-w64-mingw32/include/c++/x86_64-w64-mingw32/bits/stdc++.h:49,
                 from 0_0_33107354_432.cpp:1:
GCC4.9.2/x86_64-w64-mingw32/include/time.h:88:10: note:                 struct tm
   struct tm {
          ^
0_0_33107354_432.cpp: In function 'int main()':
0_0_33107354_432.cpp:162:3: error: reference to 'tm' is ambiguous
   tm = 0;
   ^
0_0_33107354_432.cpp:9:5: note: candidates are: int tm
 int tm;
     ^
In file included from GCC4.9.2/x86_64-w64-mingw32/include/c++/ctime:42:0,
                 from GCC4.9.2/x86_64-w64-mingw32/include/c++/x86_64-w64-mingw32/bits/stdc++.h:49,
                 from 0_0_33107354_432.cpp:1:
GCC4.9.2/x86_64-w64-mingw32/include/time.h:88:10: note:                 struct tm
   struct tm {
          ^