; LLVM IR from seikhchilli/codeforces-solution :: 1567B (main)

; Unoptimized IR (clang -disable-llvm-passes):
target datalayout = "e-m:e-p270:32:32-p271:32:32-p272:64:64-i64:64-i128:128-f80:128-n8:16:32:64-S128"
target triple = "x86_64-unknown-linux-gnu"

%"class.std::basic_istream" = type { ptr, i64, %"class.std::basic_ios" }
%"class.std::basic_ios" = type { %"class.std::ios_base", ptr, i8, i8, ptr, ptr, ptr, ptr }
%"class.std::ios_base" = type { ptr, i64, i64, i32, i32, i32, ptr, %"struct.std::ios_base::_Words", [8 x %"struct.std::ios_base::_Words"], i32, ptr, %"class.std::locale" }
%"struct.std::ios_base::_Words" = type { ptr, i64 }
%"class.std::locale" = type { ptr }
%"class.std::basic_ostream" = type { ptr, %"class.std::basic_ios" }

@_ZSt3cin = external global %"class.std::basic_istream", align 8
@_ZSt4cout = external global %"class.std::basic_ostream", align 8

; Function Attrs: mustprogress norecurse uwtable
define dso_local noundef i32 @main() #0 {
  %1 = alloca i32, align 4
  %2 = alloca i32, align 4
  %3 = alloca i32, align 4
  %4 = alloca i32, align 4
  %5 = alloca i32, align 4
  %6 = alloca i32, align 4
  store i32 0, ptr %1, align 4
  %7 = call noundef zeroext i1 @_ZNSt8ios_base15sync_with_stdioEb(i1 noundef zeroext false)
  %8 = load ptr, ptr @_ZSt3cin, align 8, !tbaa !5
  %9 = getelementptr i8, ptr %8, i64 -24
  %10 = load i64, ptr %9, align 8
  %11 = getelementptr inbounds i8, ptr @_ZSt3cin, i64 %10
  %12 = call noundef ptr @_ZNSt9basic_iosIcSt11char_traitsIcEE3tieEPSo(ptr noundef nonnull align 8 dereferenceable(264) %11, ptr noundef null)
  call void @llvm.lifetime.start.p0(i64 4, ptr %2) #5
  %13 = call noundef nonnull align 8 dereferenceable(16) ptr @_ZNSirsERi(ptr noundef nonnull align 8 dereferenceable(16) @_ZSt3cin, ptr noundef nonnull align 4 dereferenceable(4) %2)
  br label %14

14:                                               ; preds = %68, %0
  %15 = load i32, ptr %2, align 4, !tbaa !8
  %16 = add nsw i32 %15, -1
  store i32 %16, ptr %2, align 4, !tbaa !8
  %17 = icmp ne i32 %15, 0
  br i1 %17, label %18, label %69

18:                                               ; preds = %14
  call void @llvm.lifetime.start.p0(i64 4, ptr %3) #5
  call void @llvm.lifetime.start.p0(i64 4, ptr %4) #5
  %19 = call noundef nonnull align 8 dereferenceable(16) ptr @_ZNSirsERi(ptr noundef nonnull align 8 dereferenceable(16) @_ZSt3cin, ptr noundef nonnull align 4 dereferenceable(4) %3)
  %20 = call noundef nonnull align 8 dereferenceable(16) ptr @_ZNSirsERi(ptr noundef nonnull align 8 dereferenceable(16) %19, ptr noundef nonnull align 4 dereferenceable(4) %4)
  call void @llvm.lifetime.start.p0(i64 4, ptr %5) #5
  call void @llvm.lifetime.start.p0(i64 4, ptr %6) #5
  %21 = load i32, ptr %3, align 4, !tbaa !8
  %22 = sub nsw i32 %21, 1
  store i32 %22, ptr %6, align 4, !tbaa !8
  %23 = load i32, ptr %6, align 4, !tbaa !8
  %24 = srem i32 %23, 4
  %25 = icmp eq i32 %24, 0
  br i1 %25, label %26, label %28

26:                                               ; preds = %18
  %27 = load i32, ptr %6, align 4, !tbaa !8
  store i32 %27, ptr %5, align 4, !tbaa !8
  br label %43

28:                                               ; preds = %18
  %29 = load i32, ptr %6, align 4, !tbaa !8
  %30 = srem i32 %29, 4
  %31 = icmp eq i32 %30, 1
  br i1 %31, label %32, label %33

32:                                               ; preds = %28
  store i32 1, ptr %5, align 4, !tbaa !8
  br label %42

33:                                               ; preds = %28
  %34 = load i32, ptr %6, align 4, !tbaa !8
  %35 = srem i32 %34, 4
  %36 = icmp eq i32 %35, 2
  br i1 %36, label %37, label %40

37:                                               ; preds = %33
  %38 = load i32, ptr %6, align 4, !tbaa !8
  %39 = add nsw i32 %38, 1
  store i32 %39, ptr %5, align 4, !tbaa !8
  br label %41

40:                                               ; preds = %33
  store i32 0, ptr %5, align 4, !tbaa !8
  br label %41

41:                                               ; preds = %40, %37
  br label %42

42:                                               ; preds = %41, %32
  br label %43

43:                                               ; preds = %42, %26
  %44 = load i32, ptr %5, align 4, !tbaa !8
  %45 = load i32, ptr %4, align 4, !tbaa !8
  %46 = icmp eq i32 %44, %45
  br i1 %46, label %47, label %51

47:                                               ; preds = %43
  %48 = load i32, ptr %3, align 4, !tbaa !8
  %49 = call noundef nonnull align 8 dereferenceable(8) ptr @_ZNSolsEi(ptr noundef nonnull align 8 dereferenceable(8) @_ZSt4cout, i32 noundef %48)
  %50 = call noundef nonnull align 8 dereferenceable(8) ptr @_ZStlsISt11char_traitsIcEERSt13basic_ostreamIcT_ES5_c(ptr noundef nonnull align 8 dereferenceable(8) %49, i8 noundef signext 10)
  br label %68

51:                                               ; preds = %43
  %52 = load i32, ptr %5, align 4, !tbaa !8
  %53 = load i32, ptr %4, align 4, !tbaa !8
  %54 = xor i32 %52, %53
  %55 = load i32, ptr %3, align 4, !tbaa !8
  %56 = icmp ne i32 %54, %55
  br i1 %56, label %57, label %62

57:                                               ; preds = %51
  %58 = load i32, ptr %3, align 4, !tbaa !8
  %59 = add nsw i32 %58, 1
  %60 = call noundef nonnull align 8 dereferenceable(8) ptr @_ZNSolsEi(ptr noundef nonnull align 8 dereferenceable(8) @_ZSt4cout, i32 noundef %59)
  %61 = call noundef nonnull align 8 dereferenceable(8) ptr @_ZStlsISt11char_traitsIcEERSt13basic_ostreamIcT_ES5_c(ptr noundef nonnull align 8 dereferenceable(8) %60, i8 noundef signext 10)
  br label %67

62:                                               ; preds = %51
  %63 = load i32, ptr %3, align 4, !tbaa !8
  %64 = add nsw i32 %63, 2
  %65 = call noundef nonnull align 8 dereferenceable(8) ptr @_ZNSolsEi(ptr noundef nonnull align 8 dereferenceable(8) @_ZSt4cout, i32 noundef %64)
  %66 = call noundef nonnull align 8 dereferenceable(8) ptr @_ZStlsISt11char_traitsIcEERSt13basic_ostreamIcT_ES5_c(ptr noundef nonnull align 8 dereferenceable(8) %65, i8 noundef signext 10)
  br label %67

67:                                               ; preds = %62, %57
  br label %68

68:                                               ; preds = %67, %47
  call void @llvm.lifetime.end.p0(i64 4, ptr %6) #5
  call void @llvm.lifetime.end.p0(i64 4, ptr %5) #5
  call void @llvm.lifetime.end.p0(i64 4, ptr %4) #5
  call void @llvm.lifetime.end.p0(i64 4, ptr %3) #5
  br label %14, !llvm.loop !11

69:                                               ; preds = %14
  call void @llvm.lifetime.end.p0(i64 4, ptr %2) #5
  %70 = load i32, ptr %1, align 4
  ret i32 %70
}

declare noundef zeroext i1 @_ZNSt8ios_base15sync_with_stdioEb(i1 noundef zeroext) #1

; Function Attrs: mustprogress nounwind uwtable
declare noundef ptr @_ZNSt9basic_iosIcSt11char_traitsIcEE3tieEPSo(ptr noundef nonnull align 8 dereferenceable(264), ptr noundef) #2 align 2

; Function Attrs: nocallback nofree nosync nounwind willreturn memory(argmem: readwrite)
declare void @llvm.lifetime.start.p0(i64 immarg, ptr nocapture) #3

declare noundef nonnull align 8 dereferenceable(16) ptr @_ZNSirsERi(ptr noundef nonnull align 8 dereferenceable(16), ptr noundef nonnull align 4 dereferenceable(4)) #1

; Function Attrs: inlinehint mustprogress uwtable
declare noundef nonnull align 8 dereferenceable(8) ptr @_ZStlsISt11char_traitsIcEERSt13basic_ostreamIcT_ES5_c(ptr noundef nonnull align 8 dereferenceable(8), i8 noundef signext) #4

declare noundef nonnull align 8 dereferenceable(8) ptr @_ZNSolsEi(ptr noundef nonnull align 8 dereferenceable(8), i32 noundef) #1

; Function Attrs: nocallback nofree nosync nounwind willreturn memory(argmem: readwrite)
declare void @llvm.lifetime.end.p0(i64 immarg, ptr nocapture) #3

attributes #0 = { mustprogress norecurse uwtable "min-legal-vector-width"="0" "no-trapping-math"="true" "stack-protector-buffer-size"="8" "target-cpu"="x86-64" "target-features"="+cmov,+cx8,+fxsr,+mmx,+sse,+sse2,+x87" "tune-cpu"="generic" }
attributes #1 = { "no-trapping-math"="true" "stack-protector-buffer-size"="8" "target-cpu"="x86-64" "target-features"="+cmov,+cx8,+fxsr,+mmx,+sse,+sse2,+x87" "tune-cpu"="generic" }
attributes #2 = { mustprogress nounwind uwtable "min-legal-vector-width"="0" "no-trapping-math"="true" "stack-protector-buffer-size"="8" "target-cpu"="x86-64" "target-features"="+cmov,+cx8,+fxsr,+mmx,+sse,+sse2,+x87" "tune-cpu"="generic" }
attributes #3 = { nocallback nofree nosync nounwind willreturn memory(argmem: readwrite) }
attributes #4 = { inlinehint mustprogress uwtable "min-legal-vector-width"="0" "no-trapping-math"="true" "stack-protector-buffer-size"="8" "target-cpu"="x86-64" "target-features"="+cmov,+cx8,+fxsr,+mmx,+sse,+sse2,+x87" "tune-cpu"="generic" }
attributes #5 = { nounwind }

!llvm.module.flags = !{!0, !1, !2, !3}
!llvm.ident = !{!4}

!0 = !{i32 1, !"wchar_size", i32 4}
!1 = !{i32 8, !"PIC Level", i32 2}
!2 = !{i32 7, !"PIE Level", i32 2}
!3 = !{i32 7, !"uwtable", i32 2}
!4 = !{!"clang version 19.1.0 (git@github.com:llvm/llvm-project.git a4bf6cd7cfb1a1421ba92bca9d017b49936c55e4)"}
!5 = !{!6, !6, i64 0}
!6 = !{!"vtable pointer", !7, i64 0}
!7 = !{!"Simple C++ TBAA"}
!8 = !{!9, !9, i64 0}
!9 = !{!"int", !10, i64 0}
!10 = !{!"omnipotent char", !7, i64 0}
!11 = distinct !{!11, !12}
!12 = !{!"llvm.loop.mustprogress"}


; Optimized IR (opt -passes='default<O3>'):
target datalayout = "e-m:e-p270:32:32-p271:32:32-p272:64:64-i64:64-i128:128-f80:128-n8:16:32:64-S128"
target triple = "x86_64-unknown-linux-gnu"

%"class.std::basic_istream" = type { ptr, i64, %"class.std::basic_ios" }
%"class.std::basic_ios" = type { %"class.std::ios_base", ptr, i8, i8, ptr, ptr, ptr, ptr }
%"class.std::ios_base" = type { ptr, i64, i64, i32, i32, i32, ptr, %"struct.std::ios_base::_Words", [8 x %"struct.std::ios_base::_Words"], i32, ptr, %"class.std::locale" }
%"struct.std::ios_base::_Words" = type { ptr, i64 }
%"class.std::locale" = type { ptr }
%"class.std::basic_ostream" = type { ptr, %"class.std::basic_ios" }

@_ZSt3cin = external global %"class.std::basic_istream", align 8
@_ZSt4cout = external global %"class.std::basic_ostream", align 8

; Function Attrs: mustprogress norecurse uwtable
define dso_local noundef i32 @main() local_unnamed_addr #0 {
  %1 = alloca i32, align 4
  %2 = alloca i32, align 4
  %3 = alloca i32, align 4
  %4 = tail call noundef zeroext i1 @_ZNSt8ios_base15sync_with_stdioEb(i1 noundef zeroext false)
  %5 = load ptr, ptr @_ZSt3cin, align 8, !tbaa !5
  %6 = getelementptr i8, ptr %5, i64 -24
  %7 = load i64, ptr %6, align 8
  %8 = getelementptr inbounds i8, ptr @_ZSt3cin, i64 %7
  %9 = tail call noundef ptr @_ZNSt9basic_iosIcSt11char_traitsIcEE3tieEPSo(ptr noundef nonnull align 8 dereferenceable(264) %8, ptr noundef null)
  call void @llvm.lifetime.start.p0(i64 4, ptr nonnull %1) #5
  %10 = call noundef nonnull align 8 dereferenceable(16) ptr @_ZNSirsERi(ptr noundef nonnull align 8 dereferenceable(16) @_ZSt3cin, ptr noundef nonnull align 4 dereferenceable(4) %1)
  %11 = load i32, ptr %1, align 4, !tbaa !8
  %12 = add nsw i32 %11, -1
  store i32 %12, ptr %1, align 4, !tbaa !8
  %.not12 = icmp eq i32 %11, 0
  br i1 %.not12, label %._crit_edge, label %.lr.ph

.lr.ph:                                           ; preds = %0, %30
  call void @llvm.lifetime.start.p0(i64 4, ptr nonnull %2) #5
  call void @llvm.lifetime.start.p0(i64 4, ptr nonnull %3) #5
  %13 = call noundef nonnull align 8 dereferenceable(16) ptr @_ZNSirsERi(ptr noundef nonnull align 8 dereferenceable(16) @_ZSt3cin, ptr noundef nonnull align 4 dereferenceable(4) %2)
  %14 = call noundef nonnull align 8 dereferenceable(16) ptr @_ZNSirsERi(ptr noundef nonnull align 8 dereferenceable(16) %13, ptr noundef nonnull align 4 dereferenceable(4) %3)
  %15 = load i32, ptr %2, align 4, !tbaa !8
  %16 = add nsw i32 %15, -1
  %17 = srem i32 %16, 4
  switch i32 %17, label %20 [
    i32 0, label %21
    i32 1, label %18
    i32 2, label %19
  ]

18:                                               ; preds = %.lr.ph
  br label %21

19:                                               ; preds = %.lr.ph
  br label %21

20:                                               ; preds = %.lr.ph
  br label %21

21:                                               ; preds = %.lr.ph, %18, %20, %19
  %.0 = phi i32 [ 1, %18 ], [ %15, %19 ], [ 0, %20 ], [ %16, %.lr.ph ]
  %22 = load i32, ptr %3, align 4, !tbaa !8
  %23 = icmp eq i32 %.0, %22
  br i1 %23, label %30, label %24

24:                                               ; preds = %21
  %25 = xor i32 %22, %.0
  %.not11 = icmp eq i32 %25, %15
  br i1 %.not11, label %28, label %26

26:                                               ; preds = %24
  %27 = add nsw i32 %15, 1
  br label %30

28:                                               ; preds = %24
  %29 = add nsw i32 %15, 2
  br label %30

30:                                               ; preds = %21, %26, %28
  %.sink13 = phi i32 [ %27, %26 ], [ %29, %28 ], [ %15, %21 ]
  %31 = call noundef nonnull align 8 dereferenceable(8) ptr @_ZNSolsEi(ptr noundef nonnull align 8 dereferenceable(8) @_ZSt4cout, i32 noundef %.sink13)
  %32 = call noundef nonnull align 8 dereferenceable(8) ptr @_ZStlsISt11char_traitsIcEERSt13basic_ostreamIcT_ES5_c(ptr noundef nonnull align 8 dereferenceable(8) %31, i8 noundef signext 10)
  call void @llvm.lifetime.end.p0(i64 4, ptr nonnull %3) #5
  call void @llvm.lifetime.end.p0(i64 4, ptr nonnull %2) #5
  %33 = load i32, ptr %1, align 4, !tbaa !8
  %34 = add nsw i32 %33, -1
  store i32 %34, ptr %1, align 4, !tbaa !8
  %.not = icmp eq i32 %33, 0
  br i1 %.not, label %._crit_edge, label %.lr.ph, !llvm.loop !11

._crit_edge:                                      ; preds = %30, %0
  call void @llvm.lifetime.end.p0(i64 4, ptr nonnull %1) #5
  ret i32 0
}

declare noundef zeroext i1 @_ZNSt8ios_base15sync_with_stdioEb(i1 noundef zeroext) local_unnamed_addr #1

; Function Attrs: mustprogress nounwind uwtable
declare noundef ptr @_ZNSt9basic_iosIcSt11char_traitsIcEE3tieEPSo(ptr noundef nonnull align 8 dereferenceable(264), ptr noundef) local_unnamed_addr #2 align 2

; Function Attrs: mustprogress nocallback nofree nosync nounwind willreturn memory(argmem: readwrite)
declare void @llvm.lifetime.start.p0(i64 immarg, ptr nocapture) #3

declare noundef nonnull align 8 dereferenceable(16) ptr @_ZNSirsERi(ptr noundef nonnull align 8 dereferenceable(16), ptr noundef nonnull align 4 dereferenceable(4)) local_unnamed_addr #1

; Function Attrs: inlinehint mustprogress uwtable
declare noundef nonnull align 8 dereferenceable(8) ptr @_ZStlsISt11char_traitsIcEERSt13basic_ostreamIcT_ES5_c(ptr noundef nonnull align 8 dereferenceable(8), i8 noundef signext) local_unnamed_addr #4

declare noundef nonnull align 8 dereferenceable(8) ptr @_ZNSolsEi(ptr noundef nonnull align 8 dereferenceable(8), i32 noundef) local_unnamed_addr #1

; Function Attrs: mustprogress nocallback nofree nosync nounwind willreturn memory(argmem: readwrite)
declare void @llvm.lifetime.end.p0(i64 immarg, ptr nocapture) #3

attributes #0 = { mustprogress norecurse uwtable "min-legal-vector-width"="0" "no-trapping-math"="true" "stack-protector-buffer-size"="8" "target-cpu"="x86-64" "target-features"="+cmov,+cx8,+fxsr,+mmx,+sse,+sse2,+x87" "tune-cpu"="generic" }
attributes #1 = { "no-trapping-math"="true" "stack-protector-buffer-size"="8" "target-cpu"="x86-64" "target-features"="+cmov,+cx8,+fxsr,+mmx,+sse,+sse2,+x87" "tune-cpu"="generic" }
attributes #2 = { mustprogress nounwind uwtable "min-legal-vector-width"="0" "no-trapping-math"="true" "stack-protector-buffer-size"="8" "target-cpu"="x86-64" "target-features"="+cmov,+cx8,+fxsr,+mmx,+sse,+sse2,+x87" "tune-cpu"="generic" }
attributes #3 = { mustprogress nocallback nofree nosync nounwind willreturn memory(argmem: readwrite) }
attributes #4 = { inlinehint mustprogress uwtable "min-legal-vector-width"="0" "no-trapping-math"="true" "stack-protector-buffer-size"="8" "target-cpu"="x86-64" "target-features"="+cmov,+cx8,+fxsr,+mmx,+sse,+sse2,+x87" "tune-cpu"="generic" }
attributes #5 = { nounwind }

!llvm.module.flags = !{!0, !1, !2, !3}
!llvm.ident = !{!4}

!0 = !{i32 1, !"wchar_size", i32 4}
!1 = !{i32 8, !"PIC Level", i32 2}
!2 = !{i32 7, !"PIE Level", i32 2}
!3 = !{i32 7, !"uwtable", i32 2}
!4 = !{!"clang version 19.1.0 (git@github.com:llvm/llvm-project.git a4bf6cd7cfb1a1421ba92bca9d017b49936c55e4)"}
!5 = !{!6, !6, i64 0}
!6 = !{!"vtable pointer", !7, i64 0}
!7 = !{!"Simple C++ TBAA"}
!8 = !{!9, !9, i64 0}
!9 = !{!"int", !10, i64 0}
!10 = !{!"omnipotent char", !7, i64 0}
!11 = distinct !{!11, !12}
!12 = !{!"llvm.loop.mustprogress"}


; Effective O3 passes: EarlyCSEPass,GlobalOptPass,InferFunctionAttrsPass,InstCombinePass,JumpThreadingPass,LoopRotatePass,LoopSimplifyPass,LoopUnrollPass,ReassociatePass,SROAPass,SimplifyCFGPass,TailCallElimPass