please tell me what's the problem in this code:

when i submitted this code, i got “wrong answer” icon…please explain what wrong answer this code is giving??

THIS IS THE PROBLEM OF “SCHOOL” PRACTICING LEVEL, PROBLEM CODE: CHRL3

#include<stdio.h>
main()
{
  long int a,move=0;
  scanf("%d",&a);
  
  long int arr[a],i,j,k;
  
  for(i=0;i<a;i++)     
  scanf("%d",&arr[i]);
  
  read1:              
  for(i=0;i<a;i++)
  {
                  long int t=0,p=i;
                  read:
                       if(arr[p+1]==arr[p]+1)
                       {
                                         p++,t++;
                                         if(p==(a-1))
                                         goto skipread;
                                         
                                         goto read;
                       
                       
                       }
                       skipread:
                                    if(t!=0)
                                    {
                                            t++;
                                            move++;
                                    
                                         for(j=i,k=p+1;j<a && k<a;j++,k++)
                                         {
                                                                   arr[j]=arr[k];
                                         }
                                         a=a-t;
                                         goto read1;
                                    }
  }
  move = move + a;
  printf("\n%d",move);
return 0;
}

The problem which I find with the code is that it is stated that the numbers should be non-decreasing which means that the numbers in the sequence should increase or remain constant but should never decrease. Hence the condition for this needs to be corrected.

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