; LLVM IR from tangjz/acm-icpc :: lydsy (1651)

; 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"

@n = external dso_local global i32, align 4
@seq = external dso_local global [1000002 x i32], align 16
@ans = external dso_local global i32, align 4
@.str = external hidden unnamed_addr constant [3 x i8], align 1
@.str.1 = external hidden unnamed_addr constant [5 x i8], align 1
@.str.2 = external hidden unnamed_addr constant [4 x i8], align 1

; 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
  store i32 0, ptr %1, align 4
  %5 = call i32 (ptr, ...) @__isoc99_scanf(ptr noundef @.str, ptr noundef @n)
  br label %6

6:                                                ; preds = %10, %0
  %7 = load i32, ptr @n, align 4, !tbaa !5
  %8 = add nsw i32 %7, -1
  store i32 %8, ptr @n, align 4, !tbaa !5
  %9 = icmp ne i32 %7, 0
  br i1 %9, label %10, label %23

10:                                               ; preds = %6
  call void @llvm.lifetime.start.p0(i64 4, ptr %2) #3
  call void @llvm.lifetime.start.p0(i64 4, ptr %3) #3
  %11 = call i32 (ptr, ...) @__isoc99_scanf(ptr noundef @.str.1, ptr noundef %2, ptr noundef %3)
  %12 = load i32, ptr %2, align 4, !tbaa !5
  %13 = sext i32 %12 to i64
  %14 = getelementptr inbounds [1000002 x i32], ptr @seq, i64 0, i64 %13
  %15 = load i32, ptr %14, align 4, !tbaa !5
  %16 = add nsw i32 %15, 1
  store i32 %16, ptr %14, align 4, !tbaa !5
  %17 = load i32, ptr %3, align 4, !tbaa !5
  %18 = add nsw i32 %17, 1
  %19 = sext i32 %18 to i64
  %20 = getelementptr inbounds [1000002 x i32], ptr @seq, i64 0, i64 %19
  %21 = load i32, ptr %20, align 4, !tbaa !5
  %22 = add nsw i32 %21, -1
  store i32 %22, ptr %20, align 4, !tbaa !5
  call void @llvm.lifetime.end.p0(i64 4, ptr %3) #3
  call void @llvm.lifetime.end.p0(i64 4, ptr %2) #3
  br label %6, !llvm.loop !9

23:                                               ; preds = %6
  call void @llvm.lifetime.start.p0(i64 4, ptr %4) #3
  store i32 1, ptr %4, align 4, !tbaa !5
  br label %24

24:                                               ; preds = %51, %23
  %25 = load i32, ptr %4, align 4, !tbaa !5
  %26 = icmp slt i32 %25, 1000002
  br i1 %26, label %28, label %27

27:                                               ; preds = %24
  call void @llvm.lifetime.end.p0(i64 4, ptr %4) #3
  br label %54

28:                                               ; preds = %24
  %29 = load i32, ptr %4, align 4, !tbaa !5
  %30 = sub nsw i32 %29, 1
  %31 = sext i32 %30 to i64
  %32 = getelementptr inbounds [1000002 x i32], ptr @seq, i64 0, i64 %31
  %33 = load i32, ptr %32, align 4, !tbaa !5
  %34 = load i32, ptr %4, align 4, !tbaa !5
  %35 = sext i32 %34 to i64
  %36 = getelementptr inbounds [1000002 x i32], ptr @seq, i64 0, i64 %35
  %37 = load i32, ptr %36, align 4, !tbaa !5
  %38 = add nsw i32 %37, %33
  store i32 %38, ptr %36, align 4, !tbaa !5
  %39 = load i32, ptr @ans, align 4, !tbaa !5
  %40 = load i32, ptr %4, align 4, !tbaa !5
  %41 = sext i32 %40 to i64
  %42 = getelementptr inbounds [1000002 x i32], ptr @seq, i64 0, i64 %41
  %43 = load i32, ptr %42, align 4, !tbaa !5
  %44 = icmp slt i32 %39, %43
  br i1 %44, label %45, label %50

45:                                               ; preds = %28
  %46 = load i32, ptr %4, align 4, !tbaa !5
  %47 = sext i32 %46 to i64
  %48 = getelementptr inbounds [1000002 x i32], ptr @seq, i64 0, i64 %47
  %49 = load i32, ptr %48, align 4, !tbaa !5
  store i32 %49, ptr @ans, align 4, !tbaa !5
  br label %50

50:                                               ; preds = %45, %28
  br label %51

51:                                               ; preds = %50
  %52 = load i32, ptr %4, align 4, !tbaa !5
  %53 = add nsw i32 %52, 1
  store i32 %53, ptr %4, align 4, !tbaa !5
  br label %24, !llvm.loop !11

54:                                               ; preds = %27
  %55 = load i32, ptr @ans, align 4, !tbaa !5
  %56 = call i32 (ptr, ...) @printf(ptr noundef @.str.2, i32 noundef %55)
  ret i32 0
}

declare i32 @__isoc99_scanf(ptr noundef, ...) #1

; Function Attrs: nocallback nofree nosync nounwind willreturn memory(argmem: readwrite)
declare void @llvm.lifetime.start.p0(i64 immarg, ptr nocapture) #2

; Function Attrs: nocallback nofree nosync nounwind willreturn memory(argmem: readwrite)
declare void @llvm.lifetime.end.p0(i64 immarg, ptr nocapture) #2

declare i32 @printf(ptr noundef, ...) #1

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 = { nocallback nofree nosync nounwind willreturn memory(argmem: readwrite) }
attributes #3 = { 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 = !{!"int", !7, i64 0}
!7 = !{!"omnipotent char", !8, i64 0}
!8 = !{!"Simple C++ TBAA"}
!9 = distinct !{!9, !10}
!10 = !{!"llvm.loop.mustprogress"}
!11 = distinct !{!11, !10}


; 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"

@n = external dso_local global i32, align 4
@seq = external dso_local local_unnamed_addr global [1000002 x i32], align 16
@ans = external dso_local local_unnamed_addr global i32, align 4
@.str = external hidden unnamed_addr constant [3 x i8], align 1
@.str.1 = external hidden unnamed_addr constant [5 x i8], align 1
@.str.2 = external hidden unnamed_addr constant [4 x i8], align 1

; Function Attrs: mustprogress nofree norecurse nounwind uwtable
define dso_local noundef i32 @main() local_unnamed_addr #0 {
  %1 = alloca i32, align 4
  %2 = alloca i32, align 4
  %3 = tail call i32 (ptr, ...) @__isoc99_scanf(ptr noundef nonnull @.str, ptr noundef nonnull @n)
  %4 = load i32, ptr @n, align 4, !tbaa !5
  %5 = add nsw i32 %4, -1
  store i32 %5, ptr @n, align 4, !tbaa !5
  %.not7 = icmp eq i32 %4, 0
  br i1 %.not7, label %.preheader, label %.lr.ph

.preheader:                                       ; preds = %.lr.ph, %0
  %ans.promoted = load i32, ptr @ans, align 4, !tbaa !5
  %.pre = load i32, ptr @seq, align 16, !tbaa !5
  br label %22

.lr.ph:                                           ; preds = %0, %.lr.ph
  call void @llvm.lifetime.start.p0(i64 4, ptr nonnull %1) #3
  call void @llvm.lifetime.start.p0(i64 4, ptr nonnull %2) #3
  %6 = call i32 (ptr, ...) @__isoc99_scanf(ptr noundef nonnull @.str.1, ptr noundef nonnull %1, ptr noundef nonnull %2)
  %7 = load i32, ptr %1, align 4, !tbaa !5
  %8 = sext i32 %7 to i64
  %9 = getelementptr inbounds [1000002 x i32], ptr @seq, i64 0, i64 %8
  %10 = load i32, ptr %9, align 4, !tbaa !5
  %11 = add nsw i32 %10, 1
  store i32 %11, ptr %9, align 4, !tbaa !5
  %12 = load i32, ptr %2, align 4, !tbaa !5
  %13 = add nsw i32 %12, 1
  %14 = sext i32 %13 to i64
  %15 = getelementptr inbounds [1000002 x i32], ptr @seq, i64 0, i64 %14
  %16 = load i32, ptr %15, align 4, !tbaa !5
  %17 = add nsw i32 %16, -1
  store i32 %17, ptr %15, align 4, !tbaa !5
  call void @llvm.lifetime.end.p0(i64 4, ptr nonnull %2) #3
  call void @llvm.lifetime.end.p0(i64 4, ptr nonnull %1) #3
  %18 = load i32, ptr @n, align 4, !tbaa !5
  %19 = add nsw i32 %18, -1
  store i32 %19, ptr @n, align 4, !tbaa !5
  %.not = icmp eq i32 %18, 0
  br i1 %.not, label %.preheader, label %.lr.ph, !llvm.loop !9

20:                                               ; preds = %30
  %21 = call i32 (ptr, ...) @printf(ptr noundef nonnull dereferenceable(1) @.str.2, i32 noundef %31)
  ret i32 0

22:                                               ; preds = %38, %.preheader
  %23 = phi i32 [ %.pre, %.preheader ], [ %35, %38 ]
  %indvars.iv = phi i64 [ 1, %.preheader ], [ %indvars.iv.next.1, %38 ]
  %24 = phi i32 [ %ans.promoted, %.preheader ], [ %39, %38 ]
  %25 = getelementptr inbounds [1000002 x i32], ptr @seq, i64 0, i64 %indvars.iv
  %26 = load i32, ptr %25, align 4, !tbaa !5
  %27 = add nsw i32 %26, %23
  store i32 %27, ptr %25, align 4, !tbaa !5
  %28 = icmp slt i32 %24, %27
  br i1 %28, label %29, label %30

29:                                               ; preds = %22
  store i32 %27, ptr @ans, align 4, !tbaa !5
  br label %30

30:                                               ; preds = %22, %29
  %31 = phi i32 [ %24, %22 ], [ %27, %29 ]
  %indvars.iv.next = add nuw nsw i64 %indvars.iv, 1
  %exitcond.not = icmp eq i64 %indvars.iv.next, 1000002
  br i1 %exitcond.not, label %20, label %32, !llvm.loop !11

32:                                               ; preds = %30
  %33 = getelementptr inbounds [1000002 x i32], ptr @seq, i64 0, i64 %indvars.iv.next
  %34 = load i32, ptr %33, align 4, !tbaa !5
  %35 = add nsw i32 %34, %27
  store i32 %35, ptr %33, align 4, !tbaa !5
  %36 = icmp slt i32 %31, %35
  br i1 %36, label %37, label %38

37:                                               ; preds = %32
  store i32 %35, ptr @ans, align 4, !tbaa !5
  br label %38

38:                                               ; preds = %37, %32
  %39 = phi i32 [ %31, %32 ], [ %35, %37 ]
  %indvars.iv.next.1 = add nuw nsw i64 %indvars.iv, 2
  br label %22
}

; Function Attrs: nofree nounwind
declare noundef i32 @__isoc99_scanf(ptr nocapture noundef readonly, ...) local_unnamed_addr #1

; Function Attrs: mustprogress nocallback nofree nosync nounwind willreturn memory(argmem: readwrite)
declare void @llvm.lifetime.start.p0(i64 immarg, ptr nocapture) #2

; Function Attrs: mustprogress nocallback nofree nosync nounwind willreturn memory(argmem: readwrite)
declare void @llvm.lifetime.end.p0(i64 immarg, ptr nocapture) #2

; Function Attrs: nofree nounwind
declare noundef i32 @printf(ptr nocapture noundef readonly, ...) local_unnamed_addr #1

attributes #0 = { mustprogress nofree norecurse 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 #1 = { nofree nounwind "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 nocallback nofree nosync nounwind willreturn memory(argmem: readwrite) }
attributes #3 = { 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 = !{!"int", !7, i64 0}
!7 = !{!"omnipotent char", !8, i64 0}
!8 = !{!"Simple C++ TBAA"}
!9 = distinct !{!9, !10}
!10 = !{!"llvm.loop.mustprogress"}
!11 = distinct !{!11, !10}


; Effective O3 passes: BDCEPass,EarlyCSEPass,GVNPass,GlobalOptPass,IndVarSimplifyPass,InferAlignmentPass,InferFunctionAttrsPass,InstCombinePass,InstSimplifyPass,JumpThreadingPass,LCSSAPass,LICMPass,LoopRotatePass,LoopSimplifyPass,LoopUnrollPass,PostOrderFunctionAttrsPass,SROAPass,SimplifyCFGPass,TailCallElimPass