program main
  implicit none
  integer :: n, i, j
  integer, allocatable :: a(:)
  read(*, *) n
  allocate(a(n))
  read(*, *) (a(i), i = 1, n)
  j = 1
  do i = 1, n
    j = a(j)
    if (j == 2) then
      write(*, "(i0)") i
      stop 0
    end if
  end do
  write(*, "(i0)") -1
end program main


; ModuleID = 'FIRModule'
source_filename = "FIRModule"
target datalayout = "e-m:e-p270:32:32-p271:32:32-p272:64:64-i64:64-f80:128-n8:16:32:64-S128"
target triple = "x86_64-pc-linux-gnu"

@_QFEa.0 = internal unnamed_addr global ptr null
@_QQcl.9d4f5230f896e49e023b83382058a9d2 = linkonce constant [73 x i8] c"/home/ubuntu/Downloads/TheStack_IR/Collated/Fortran/Source_7177/source.f\00"
@_QQcl.28693029 = linkonce constant [4 x i8] c"(i0)"
@_QQEnvironmentDefaults = local_unnamed_addr constant ptr null

; Function Attrs: mustprogress nofree nounwind willreturn allockind("alloc,uninitialized") allocsize(0) memory(inaccessiblemem: readwrite)
declare noalias noundef ptr @malloc(i64 noundef) local_unnamed_addr #0

define void @_QQmain() local_unnamed_addr {
  %1 = alloca i32, align 4
  %2 = tail call ptr @_FortranAioBeginExternalListInput(i32 -1, ptr nonnull @_QQcl.9d4f5230f896e49e023b83382058a9d2, i32 5)
  %3 = call i1 @_FortranAioInputInteger(ptr %2, ptr nonnull %1, i32 4)
  %4 = call i32 @_FortranAioEndIoStatement(ptr %2)
  %5 = load i32, ptr %1, align 4, !tbaa !3
  %6 = call i32 @llvm.smax.i32(i32 %5, i32 0)
  %7 = zext i32 %6 to i64
  %8 = shl nuw nsw i64 %7, 2
  %9 = call ptr @malloc(i64 %8)
  store ptr %9, ptr @_QFEa.0, align 8, !tbaa !7
  %10 = call ptr @_FortranAioBeginExternalListInput(i32 -1, ptr nonnull @_QQcl.9d4f5230f896e49e023b83382058a9d2, i32 7)
  %11 = load i32, ptr %1, align 4, !tbaa !3
  %12 = icmp sgt i32 %11, 0
  br i1 %12, label %.lr.ph.preheader, label %._crit_edge

.lr.ph.preheader:                                 ; preds = %0
  %13 = zext i32 %11 to i64
  br label %.lr.ph

.lr.ph:                                           ; preds = %.lr.ph.preheader, %.lr.ph
  %14 = phi i64 [ %19, %.lr.ph ], [ 1, %.lr.ph.preheader ]
  %.unpack78 = load ptr, ptr @_QFEa.0, align 8, !tbaa !7
  %sext = shl i64 %14, 32
  %15 = ashr exact i64 %sext, 32
  %16 = add nsw i64 %15, -1
  %17 = getelementptr i32, ptr %.unpack78, i64 %16
  %18 = call i1 @_FortranAioInputInteger(ptr %10, ptr %17, i32 4)
  %19 = add nuw nsw i64 %14, 1
  %exitcond.not = icmp eq i64 %14, %13
  br i1 %exitcond.not, label %._crit_edge, label %.lr.ph

._crit_edge:                                      ; preds = %.lr.ph, %0
  %20 = call i32 @_FortranAioEndIoStatement(ptr %10)
  %21 = load i32, ptr %1, align 4, !tbaa !3
  %22 = icmp sgt i32 %21, 0
  br i1 %22, label %.lr.ph95, label %._crit_edge96

.lr.ph95:                                         ; preds = %._crit_edge
  %.unpack = load ptr, ptr @_QFEa.0, align 8, !tbaa !7
  br label %23

23:                                               ; preds = %.lr.ph95, %34
  %.093 = phi i32 [ 1, %.lr.ph95 ], [ %27, %34 ]
  %.05492 = phi i32 [ 1, %.lr.ph95 ], [ %35, %34 ]
  %24 = sext i32 %.093 to i64
  %25 = add nsw i64 %24, -1
  %26 = getelementptr i32, ptr %.unpack, i64 %25
  %27 = load i32, ptr %26, align 4, !tbaa !3
  %28 = icmp eq i32 %27, 2
  br i1 %28, label %29, label %34

29:                                               ; preds = %23
  %30 = call ptr @_FortranAioBeginExternalFormattedOutput(ptr nonnull @_QQcl.28693029, i64 4, ptr null, i32 -1, ptr nonnull @_QQcl.9d4f5230f896e49e023b83382058a9d2, i32 12)
  %31 = call i1 @_FortranAioOutputInteger32(ptr %30, i32 %.05492)
  %32 = call i32 @_FortranAioEndIoStatement(ptr %30)
  %33 = call {} @_FortranAStopStatement(i32 0, i1 false, i1 false)
  unreachable

34:                                               ; preds = %23
  %35 = add nuw i32 %.05492, 1
  %exitcond98.not = icmp eq i32 %.05492, %21
  br i1 %exitcond98.not, label %._crit_edge96, label %23

._crit_edge96:                                    ; preds = %34, %._crit_edge
  %36 = call ptr @_FortranAioBeginExternalFormattedOutput(ptr nonnull @_QQcl.28693029, i64 4, ptr null, i32 -1, ptr nonnull @_QQcl.9d4f5230f896e49e023b83382058a9d2, i32 16)
  %37 = call i1 @_FortranAioOutputInteger32(ptr %36, i32 -1)
  %38 = call i32 @_FortranAioEndIoStatement(ptr %36)
  ret void
}

declare ptr @_FortranAioBeginExternalListInput(i32, ptr, i32) local_unnamed_addr

declare i1 @_FortranAioInputInteger(ptr, ptr, i32) local_unnamed_addr

declare i32 @_FortranAioEndIoStatement(ptr) local_unnamed_addr

declare ptr @_FortranAioBeginExternalFormattedOutput(ptr, i64, ptr, i32, ptr, i32) local_unnamed_addr

declare i1 @_FortranAioOutputInteger32(ptr, i32) local_unnamed_addr

declare {} @_FortranAStopStatement(i32, i1, i1) local_unnamed_addr

; Function Attrs: nocallback nofree nosync nounwind speculatable willreturn memory(none)
declare i32 @llvm.smax.i32(i32, i32) #1

attributes #0 = { mustprogress nofree nounwind willreturn allockind("alloc,uninitialized") allocsize(0) memory(inaccessiblemem: readwrite) "alloc-family"="malloc" }
attributes #1 = { nocallback nofree nosync nounwind speculatable willreturn memory(none) }

!llvm.module.flags = !{!0, !1, !2}

!0 = !{i32 2, !"Debug Info Version", i32 3}
!1 = !{i32 8, !"PIC Level", i32 2}
!2 = !{i32 7, !"PIE Level", i32 2}
!3 = !{!4, !4, i64 0}
!4 = !{!"any data access", !5, i64 0}
!5 = !{!"any access", !6, i64 0}
!6 = !{!"Flang Type TBAA Root"}
!7 = !{!8, !8, i64 0}
!8 = !{!"descriptor member", !5, i64 0}
