; LLVM IR from tangjz/acm-icpc :: 51nod (1400)

; 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"

@t = external dso_local global i32, align 4
@n = external dso_local global i32, align 4
@a = external dso_local global [50 x i32], align 16
@b = external dso_local global [50 x i32], align 16
@.str = external hidden unnamed_addr constant [3 x i8], align 1
@.str.1 = external hidden unnamed_addr constant [11 x i8], align 1
@.str.2 = external hidden unnamed_addr constant [13 x i8], align 1

; Function Attrs: mustprogress uwtable
declare dso_local noundef zeroext i1 @_Z3dfsiii(i32 noundef, i32 noundef, i32 noundef) #0

; Function Attrs: mustprogress norecurse uwtable
define dso_local noundef i32 @main() #1 {
  %1 = alloca i32, align 4
  %2 = alloca i32, align 4
  store i32 0, ptr %1, align 4
  %3 = call i32 (ptr, ...) @__isoc99_scanf(ptr noundef @.str, ptr noundef @t)
  br label %4

4:                                                ; preds = %23, %0
  %5 = load i32, ptr @t, align 4, !tbaa !5
  %6 = add nsw i32 %5, -1
  store i32 %6, ptr @t, align 4, !tbaa !5
  %7 = icmp sgt i32 %5, 0
  br i1 %7, label %8, label %29

8:                                                ; preds = %4
  %9 = call i32 (ptr, ...) @__isoc99_scanf(ptr noundef @.str, ptr noundef @n)
  call void @llvm.lifetime.start.p0(i64 4, ptr %2) #4
  store i32 0, ptr %2, align 4, !tbaa !5
  br label %10

10:                                               ; preds = %20, %8
  %11 = load i32, ptr %2, align 4, !tbaa !5
  %12 = load i32, ptr @n, align 4, !tbaa !5
  %13 = icmp slt i32 %11, %12
  br i1 %13, label %15, label %14

14:                                               ; preds = %10
  call void @llvm.lifetime.end.p0(i64 4, ptr %2) #4
  br label %23

15:                                               ; preds = %10
  %16 = load i32, ptr %2, align 4, !tbaa !5
  %17 = sext i32 %16 to i64
  %18 = getelementptr inbounds i32, ptr @a, i64 %17
  %19 = call i32 (ptr, ...) @__isoc99_scanf(ptr noundef @.str, ptr noundef %18)
  br label %20

20:                                               ; preds = %15
  %21 = load i32, ptr %2, align 4, !tbaa !5
  %22 = add nsw i32 %21, 1
  store i32 %22, ptr %2, align 4, !tbaa !5
  br label %10, !llvm.loop !9

23:                                               ; preds = %14
  %24 = load i32, ptr @a, align 16, !tbaa !5
  store i32 %24, ptr @b, align 16, !tbaa !5
  %25 = call noundef zeroext i1 @_Z3dfsiii(i32 noundef 1, i32 noundef 1, i32 noundef 0)
  %26 = zext i1 %25 to i64
  %27 = select i1 %25, ptr @.str.1, ptr @.str.2
  %28 = call i32 @puts(ptr noundef %27)
  br label %4, !llvm.loop !11

29:                                               ; preds = %4
  ret i32 0
}

declare i32 @__isoc99_scanf(ptr noundef, ...) #2

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

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

declare i32 @puts(ptr noundef) #2

attributes #0 = { 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 #1 = { 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 #2 = { "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 = { 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"

@t = external dso_local global i32, align 4
@n = external dso_local global i32, align 4
@a = external dso_local global [50 x i32], align 16
@b = external dso_local local_unnamed_addr global [50 x i32], align 16
@.str = external hidden unnamed_addr constant [3 x i8], align 1
@.str.1 = external hidden unnamed_addr constant [11 x i8], align 1
@.str.2 = external hidden unnamed_addr constant [13 x i8], align 1

; Function Attrs: mustprogress uwtable
declare dso_local noundef zeroext i1 @_Z3dfsiii(i32 noundef, i32 noundef, i32 noundef) local_unnamed_addr #0

; Function Attrs: mustprogress norecurse uwtable
define dso_local noundef i32 @main() local_unnamed_addr #1 {
  %1 = tail call i32 (ptr, ...) @__isoc99_scanf(ptr noundef nonnull @.str, ptr noundef nonnull @t)
  %2 = load i32, ptr @t, align 4, !tbaa !5
  %3 = add nsw i32 %2, -1
  store i32 %3, ptr @t, align 4, !tbaa !5
  %4 = icmp sgt i32 %2, 0
  br i1 %4, label %.lr.ph5, label %._crit_edge6

.lr.ph5:                                          ; preds = %0, %._crit_edge
  %5 = tail call i32 (ptr, ...) @__isoc99_scanf(ptr noundef nonnull @.str, ptr noundef nonnull @n)
  %6 = load i32, ptr @n, align 4, !tbaa !5
  %7 = icmp sgt i32 %6, 0
  br i1 %7, label %.lr.ph, label %._crit_edge

._crit_edge:                                      ; preds = %.lr.ph, %.lr.ph5
  %8 = load i32, ptr @a, align 16, !tbaa !5
  store i32 %8, ptr @b, align 16, !tbaa !5
  %9 = tail call noundef zeroext i1 @_Z3dfsiii(i32 noundef 1, i32 noundef 1, i32 noundef 0)
  %10 = select i1 %9, ptr @.str.1, ptr @.str.2
  %11 = tail call i32 @puts(ptr noundef nonnull dereferenceable(1) %10)
  %12 = load i32, ptr @t, align 4, !tbaa !5
  %13 = add nsw i32 %12, -1
  store i32 %13, ptr @t, align 4, !tbaa !5
  %14 = icmp sgt i32 %12, 0
  br i1 %14, label %.lr.ph5, label %._crit_edge6, !llvm.loop !9

.lr.ph:                                           ; preds = %.lr.ph5, %.lr.ph
  %indvars.iv = phi i64 [ %indvars.iv.next, %.lr.ph ], [ 0, %.lr.ph5 ]
  %15 = getelementptr inbounds i32, ptr @a, i64 %indvars.iv
  %16 = tail call i32 (ptr, ...) @__isoc99_scanf(ptr noundef nonnull @.str, ptr noundef nonnull %15)
  %indvars.iv.next = add nuw nsw i64 %indvars.iv, 1
  %17 = load i32, ptr @n, align 4, !tbaa !5
  %18 = sext i32 %17 to i64
  %19 = icmp slt i64 %indvars.iv.next, %18
  br i1 %19, label %.lr.ph, label %._crit_edge, !llvm.loop !11

._crit_edge6:                                     ; preds = %._crit_edge, %0
  ret i32 0
}

; Function Attrs: nofree nounwind
declare noundef i32 @__isoc99_scanf(ptr nocapture noundef readonly, ...) local_unnamed_addr #2

; Function Attrs: nofree nounwind
declare noundef i32 @puts(ptr nocapture noundef readonly) local_unnamed_addr #2

attributes #0 = { 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 #1 = { 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 #2 = { 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" }

!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: EarlyCSEPass,GlobalOptPass,IndVarSimplifyPass,InferFunctionAttrsPass,InstCombinePass,JumpThreadingPass,LoopRotatePass,LoopSimplifyPass,LoopUnrollPass,SROAPass,SimplifyCFGPass,TailCallElimPass