View Compilation Error

0_0_39175531_2828.cpp: In function 'void addtag(int, int, int, int)':
0_0_39175531_2828.cpp:41:35: error: ISO C++ forbids comparison between pointer and integer [-fpermissive]
   41 |     if(x == 2 && (tag == 0 || tag == 1)) tag[p] = 1 - tag[p];
      |                               ~~~~^~~~