Please fix error in this code. This code is from queue topic , wriiten in c.i tried so many things but still not able to fix the errors.

  1  #include <stdio.h>
  2  #include <stdlib.h>
  3  
  4  #define QUEUE_SIZE 5
  5  
  6  struct queue
  7  {
  8      int items[QUEUE_SIZE];
  9      int front;
 10      int rear;
 11  };
 12  
 13  typedef struct queue QUEUE;
 14  
 15  int insert_rear(int item, QUEUE *q)
 16  {
 17      if (q->rear == QUEUE_SIZE - 1)
 18      {
 19          printf("\nQueue is full , insertion at rear end is not possible ");
 20          return 0;
 21      }
 22      (q->rear)++;
 23      q->items[q->rear] = item;
 24  };
 25  
 26  int delete_front(QUEUE *q)
 27  {
 28      if (q->front > q->rear)
 29      {
 30          printf("\nQueue is empty,deletion is not possible");
 31          return 0;
 32      }
 33      printf("the element deleted is %d\n", q->items[q->front]);
 34      (q->front)++;
 35  
 36      if (q->front > q->rear)
 37      {
 38          q->front = 0;
 39          q->rear = -1;
 40      }
 41  }
 42  
 43  int display(QUEUE *q)
 44  {
 45      int i;
 46      if (q->front > q->rear)
 47      {
 48          printf("\nQueue is empty,can't display the contents");
 49          return 0;
 50      }
 51      printf("\nThe Queue contents are:\n");
 52  
 53      for (i = q->front; i <= q->rear; i++)
 54      {
 55          printf("%d\t", q->items[i]);
 56      }
 57      int main()
 58      {
 59          QUEUE q;
 60          q.front = 0;
 61          q.rear = -1;
 62          int input, item;
 63          for (;;)
 64          {
 65              printf("\n1 to insert rear");
 66              printf("\n2 to delte front");
 67              printf("\n3 to display content of the queue");
 68              printf("\n4 to exit");
 69              printf("\n1 enter the choice:");
 70              scanf("%d", &input);
 71              switch (input)
 72              {
 73              case 1:
 74                  printf("\nEnter the item to be inserted:");
 75                  scanf("%d", &item);
 76                  insert_rear(item, &q);
 77                  display(&q);
 78                  break;
 79  
 80              case 2:
 81                  delete_front(&q);
 82                  display(&q);
 83                  break;
 84  
 85              case 3:
 86                  display(&q);
 87                  break;
 88  
 89              case 4:
 90                  exit(0);
 91                  break;
 92  
 93              default:
 94                  printf("\n invaid choice");
 95                  continue;
 96              }
 97          }
 98      }

int main();
    {
        QUEUE q;
        q.front = 0;
        q.rear = -1;
        int input, item;
        for (;;)
        {
            printf("\n1 to insert rear");
            printf("\n2 to delte front");
            printf("\n3 to display content of the queue");
            printf("\n4 to exit");
            printf("\n1 enter the choice:");
            scanf("%d", &input);
            switch (input)
            {
            case 1:
                printf("\nEnter the item to be inserted:");
                scanf("%d", &item);
                insert_rear(item, &q);
                display(&q);
                break;

            case 2:
                delete_front(&q);
                display(&q);
                break;

            case 3:
                display(&q);
                break;

            case 4:
                exit(0);
                break;

            default:
                printf("\n invaid choice");
                continue;
            }
        }
    }