View Compilation Error

0_0_27110258_11026.c:6:6: error: variably modified 'ch' at file scope
  int ch[maxnode][sigma_size];
      ^
0_0_27110258_11026.c:6:6: error: variably modified 'ch' at file scope
0_0_27110258_11026.c:8:6: error: variably modified 'num' at file scope
  int num[maxnode];
      ^
0_0_27110258_11026.c:9:2: error: expected specifier-qualifier-list before 'Trie'
  Trie(){ 
  ^
0_0_27110258_11026.c:47:1: error: unknown type name 'Trie'
 Trie T;
 ^
0_0_27110258_11026.c: In function 'main':
0_0_27110258_11026.c:55:4: error: request for member 'insert' in something not a structure or union
   T.insert(s,1);
    ^
0_0_27110258_11026.c:59:18: error: request for member 'search' in something not a structure or union
   printf("%d\n",T.search(s));
                  ^