foo.c:7:9: error: unknown type name 'QueueNode'
    7 |         QueueNode* next;
      |         ^~~~~~~~~
foo.c:8:9: error: expected specifier-qualifier-list before 'QueueNode'
    8 |         QueueNode(int data,int Index)
      |         ^~~~~~~~~
foo.c:16:1: error: unknown type name 'class'
   16 | class Queue{
      | ^~~~~
foo.c:16:12: error: expected '=', ',', ';', 'asm' or '__attribute__' before '{' token
   16 | class Queue{
      |            ^
foo.c: In function 'main':
foo.c:47:5: error: unknown type name 'Queue'
   47 |     Queue* q=new Queue();
      |     ^~~~~
foo.c:47:14: error: 'new' undeclared (first use in this function)
   47 |     Queue* q=new Queue();
      |              ^~~
foo.c:47:14: note: each undeclared identifier is reported only once for each function it appears in
foo.c:47:18: error: expected ',' or ';' before 'Queue'
   47 |     Queue* q=new Queue();
      |                  ^~~~~
foo.c:48:6: error: request for member 'InitQueue' in something not a structure or union
   48 |     q->InitQueue(x);
      |      ^~
foo.c:52:10: error: request for member 'InsertQueue' in something not a structure or union
   52 |         q->InsertQueue(x);
      |          ^~
foo.c:55:20: error: request for member 'Search' in something not a structure or union
   55 |         int index=q->Search(x);
      |                    ^~

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