View Compilation Error

0_0_39462973_8976.cpp:19:8: error: expected initializer before '*' token
   19 | } st[N]*4;
      |        ^
0_0_39462973_8976.cpp: In function 'void merge(int, int)':
0_0_39462973_8976.cpp:32:9: error: 'st' was not declared in this scope; did you mean 't'?
   32 |         st[++top] = {x, y, height[x] == height[y]};
      |         ^~
      |         t
0_0_39462973_8976.cpp: In function 'void fenzhi(int, int, int)':
0_0_39462973_8976.cpp:64:24: error: 'st' was not declared in this scope; did you mean 't'?
   64 |                 height[st[top].y] -= st[top].add;
      |                        ^~
      |                        t