View Compilation Error

0_0_21600684_5685.cpp: In function 'void pushdown(int)':
0_0_21600684_5685.cpp:3:8: error: 'cover' was not declared in this scope
     if(cover[o] != -1)
        ^
0_0_21600684_5685.cpp:6:9: error: 'XO' was not declared in this scope
         XO[o << 1] = XO[o << 1 | 1] = 0;
         ^
0_0_21600684_5685.cpp:9:8: error: 'XO' was not declared in this scope
     if(XO[o])
        ^
0_0_21600684_5685.cpp:11:19: error: 'FOX' was not declared in this scope
         FOX(o << 1);
                   ^