Problem:
Score : 100 points

Problem Statement

You are given a string of length N. Calculate the number of distinct substrings of S.

Constraints

1 \leq N \leq 500,000

S consists of lowercase English letters.

Input

Input is given from Standard Input in the following format:

S

Output

Print the answer.

Sample Input 1

abcbcba

Sample Output 1

21

Sample Input 2

mississippi

Sample Output 2

53

Sample Input 3

ababacaca

Sample Output 3

33

Sample Input 4

aaaaa

Sample Output 4

5

Solution in C# (.NET Core 3.1.201) (judge verdict: Accepted)

using System;
using System.Collections;
using System.Collections.Generic;
using System.Diagnostics;
using System.Globalization;
using System.IO;
using System.Linq;
using System.Numerics;
using System.Reflection.Metadata;
using System.Runtime.CompilerServices;
using System.Runtime.InteropServices;
using System.Runtime.Intrinsics.X86;
using System.Text;
using System.Text.RegularExpressions;
using System.Threading;

namespace AtCoder
{
	public class Program
	{
		static void Main()
		{
			using var cin = new Scanner();
			string s = cin.Next();
			long n = s.Length;

			long ans = n * (n + 1) / 2;
			var sa = StringAlgorithm.SuffixArray(s);
			var la = StringAlgorithm.LcpArray(s, sa);
			foreach (var lcp in la) {
				ans -= lcp;
			}

			Console.WriteLine(ans);
		}
	}

	public static class StringAlgorithm
	{
		public class StringComparator : IComparer<string>
		{
			int IComparer<string>.Compare(string a, string b)
			{
				int length = Math.Min(a.Length, b.Length);
				for (int i = 0; i < length; i++) {
					if (a[i] < b[i]) {
						return -1;
					} else if (a[i] > b[i]) {
						return 1;
					}
				}

				if (a.Length < b.Length) {
					return -1;
				}

				if (a.Length > b.Length) {
					return 1;
				}

				return 0;
			}
		}

		public static int[] ZAlogorithm(string s, int start)
		{
			int n = s.Length - start;
			int[] a = new int[n];
			int c = 0;
			for (int i = 1; i < n; i++) {
				if (i + a[i - c] < c + a[c]) {
					a[i] = a[i - c];
				} else {
					int j = Math.Max(0, c + a[c] - i);
					while (i + j < n && s[j + start] == s[i + j + start]) {
						++j;
					}
					a[i] = j;
					c = i;
				}
			}

			a[0] = n;
			return a;
		}

		//original: ttps://github.com/key-moon/ac-library-cs
		public static int[] ZAlgorithm(string s) => ZAlgorithm(s.AsSpan());
		public static int[] ZAlgorithm<T>(T[] s) => ZAlgorithm((ReadOnlySpan<T>)s);
		public static int[] ZAlgorithm<T>(ReadOnlySpan<T> s)
		{
			int n = s.Length;
			if (n == 0) {
				return new int[] { };
			}

			int[] z = new int[n];
			z[0] = 0;
			for (int i = 1, j = 0; i < n; ++i) {
				ref int k = ref z[i];
				k = (j + z[j] <= i) ? 0 : Math.Min(j + z[j] - i, z[i - j]);
				while (i + k < n && EqualityComparer<T>.Default.Equals(s[k], s[i + k])) {
					++k;
				}

				if (j + z[j] < i + z[i]) {
					j = i;
				}
			}

			z[0] = n;
			return z;
		}

		//original: ttps://github.com/key-moon/ac-library-cs
		public static int[] SuffixArray(string s)
			=> SAIS(s.Select(c => (int)c).ToArray(), char.MaxValue);
		public static int[] SAIS(ReadOnlyMemory<int> memory, int upper) => SAIS(memory, upper, 10, 40);
		public static int[] SAIS(ReadOnlyMemory<int> memory, int upper, int thresholdNaive, int thresholdDouling)
		{
			var s = memory.Span;
			var n = s.Length;
			if (n == 0) {
				return Array.Empty<int>();
			} else if (n == 1) {
				return new int[] { 0 };
			} else if (n == 2) {
				if (s[0] < s[1]) {
					return new int[] { 0, 1 };
				} else {
					return new int[] { 1, 0 };
				}
			} else if (n < thresholdNaive) {
				return SANaive(memory);
			} else if (n < thresholdDouling) {
				return SADoubling(memory);
			}

			var sa = new int[n];
			var isTypeS = new bool[n];
			for (int i = sa.Length - 2; i >= 0; --i) {
				isTypeS[i] = (s[i] == s[i + 1]) ? isTypeS[i + 1] : (s[i] < s[i + 1]);
			}

			var sumL = new int[upper + 1];
			var sumS = new int[upper + 1];

			for (int i = 0; i < s.Length; ++i) {
				if (!isTypeS[i]) {
					++sumS[s[i]];
				} else {
					++sumL[s[i] + 1];
				}
			}

			for (int i = 0; i < sumL.Length; ++i) {
				sumS[i] += sumL[i];
				if (i < upper) {
					sumL[i + 1] += sumS[i];
				}
			}

			var lmsMap = new int[n + 1];
			lmsMap.AsSpan().Fill(-1);
			int m = 0;
			for (int i = 1; i < isTypeS.Length; ++i) {
				if (!isTypeS[i - 1] && isTypeS[i]) {
					lmsMap[i] = m;
					++m;
				}
			}

			var lms = new List<int>(m);
			for (int i = 1; i < isTypeS.Length; ++i) {
				if (!isTypeS[i - 1] && isTypeS[i]) {
					lms.Add(i);
				}
			}

			void Induce(List<int> lms)
			{
				var s = memory.Span;
				sa.AsSpan().Fill(-1);
				var buf = new int[sumS.Length];

				sumS.AsSpan().CopyTo(buf);
				foreach (var d in lms) {
					if (d == n) {
						continue;
					}

					sa[buf[s[d]]] = d;
					++buf[s[d]];
				}

				sumL.AsSpan().CopyTo(buf);
				sa[buf[s[n - 1]]] = n - 1;
				++buf[s[n - 1]];
				for (int i = 0; i < sa.Length; ++i) {
					int v = sa[i];
					if (v >= 1 && !isTypeS[v - 1]) {
						sa[buf[s[v - 1]]] = v - 1;
						++buf[s[v - 1]];
					}
				}

				sumL.AsSpan().CopyTo(buf);
				for (int i = sa.Length - 1; i >= 0; --i) {
					int v = sa[i];
					if (v >= 1 && isTypeS[v - 1]) {
						--buf[s[v - 1] + 1];
						sa[buf[s[v - 1] + 1]] = v - 1;
					}
				}
			}

			Induce(lms);

			if (m > 0) {
				var sortedLms = new List<int>(m);
				foreach (var v in sa) {
					if (lmsMap[v] != -1) {
						sortedLms.Add(v);
					}
				}

				var recS = new int[m];
				var recUpper = 0;
				recS[lmsMap[sortedLms[0]]] = 0;
				for (int i = 1; i < sortedLms.Count; i++) {
					var l = sortedLms[i - 1];
					var r = sortedLms[i];
					var endL = (lmsMap[l] + 1 < m) ? lms[lmsMap[l] + 1] : n;
					var endR = (lmsMap[r] + 1 < m) ? lms[lmsMap[r] + 1] : n;
					var same = true;

					if (endL - l != endR - r) {
						same = false;
					} else {
						while (l < endL) {
							if (s[l] != s[r]) {
								break;
							}

							++l;
							++r;
						}

						if (l == n || s[l] != s[r]) {
							same = false;
						}
					}

					if (!same) {
						++recUpper;
					}

					recS[lmsMap[sortedLms[i]]] = recUpper;
				}

				var recSA = SAIS(recS, recUpper, thresholdNaive, thresholdDouling);
				for (int i = 0; i < sortedLms.Count; ++i) {
					sortedLms[i] = lms[recSA[i]];
				}

				Induce(sortedLms);
			}

			return sa;
		}

		private static int[] SANaive(ReadOnlyMemory<int> memory)
		{
			var n = memory.Length;
			var sa = Enumerable.Range(0, n).ToArray();

			int Compare(int l, int r)
			{
				var s = memory.Span;
				while (l < s.Length && r < s.Length) {
					if (s[l] != s[r]) {
						return s[l] - s[r];
					}

					++l;
					++r;
				}

				return r - l;
			}

			Array.Sort(sa, Compare);
			return sa;
		}

		private static int[] SADoubling(ReadOnlyMemory<int> memory)
		{
			var s = memory.Span;
			var n = s.Length;
			var sa = Enumerable.Range(0, n).ToArray();
			var rnk = new int[n];
			var tmp = new int[n];
			s.CopyTo(rnk);

			for (int k = 1; k < n; k <<= 1) {
				int Compare(int x, int y)
				{
					if (rnk[x] != rnk[y]) {
						return rnk[x] - rnk[y];
					}

					int rx = x + k < n ? rnk[x + k] : -1;
					int ry = y + k < n ? rnk[y + k] : -1;

					return rx - ry;
				}

				Array.Sort(sa, Compare);
				tmp[sa[0]] = 0;
				for (int i = 1; i < sa.Length; ++i) {
					tmp[sa[i]] = tmp[sa[i - 1]] + (Compare(sa[i - 1], sa[i]) < 0 ? 1 : 0);
				}

				(tmp, rnk) = (rnk, tmp);
			}

			return sa;
		}

		//original: ttps://github.com/key-moon/ac-library-cs
		public static int[] LcpArray(string s, int[] saffixArray) => LcpArray(s.AsSpan(), saffixArray);
		public static int[] LcpArray<T>(T[] s, int[] saffixArray) => LcpArray((ReadOnlySpan<T>)s, saffixArray);
		public static int[] LcpArray<T>(ReadOnlySpan<T> s, int[] saffixArray)
		{
			int[] rnk = new int[s.Length];
			for (int i = 0; i < s.Length; ++i) {
				rnk[saffixArray[i]] = i;
			}

			int[] lcp = new int[s.Length - 1];
			int h = 0;
			for (int i = 0; i < s.Length; ++i) {
				if (h > 0) {
					--h;
				}

				if (rnk[i] == 0) {
					continue;
				}

				int j = saffixArray[rnk[i] - 1];
				for (; j + h < s.Length && i + h < s.Length; ++h) {
					if (!EqualityComparer<T>.Default.Equals(s[j + h], s[i + h])) {
						break;
					}
				}

				lcp[rnk[i] - 1] = h;
			}

			return lcp;
		}
	}

	public class HashMap<TKey, TValue> : Dictionary<TKey, TValue>
	{
		private readonly Func<TKey, TValue> initialzier_;
		public HashMap(Func<TKey, TValue> initialzier)
			: base()
		{
			initialzier_ = initialzier;
		}

		public HashMap(Func<TKey, TValue> initialzier, int capacity)
			: base(capacity)
		{
			initialzier_ = initialzier;
		}

		new public TValue this[TKey key]
		{
			get
			{
				if (ContainsKey(key) == false) {
					base[key] = initialzier_(key);
				}

				return base[key];
			}

			set { base[key] = value; }
		}
	}

	public struct ModInt
	{
		//public const long P = 1000000007;
		public const long P = 998244353;
		public const long ROOT = 3;

		// (924844033, 5)
		// (998244353, 3)
		// (1012924417, 5)
		// (167772161, 3)
		// (469762049, 3)
		// (1224736769, 3)

		public static ModInt Inverse(ModInt value) => Pow(value, P - 2);
		public static ModInt Pow(ModInt value, long k) => Pow(value.value_, k);
		public static ModInt Pow(long value, long k)
		{
			long ret = 1;
			for (k %= P - 1; k > 0; k >>= 1, value = value * value % P) {
				if ((k & 1) == 1) {
					ret = ret * value % P;
				}
			}
			return new ModInt(ret);
		}

		private long value_;

		public ModInt(long value)
			=> value_ = value;
		public ModInt(long value, bool mods)
		{
			if (mods) {
				value %= P;
				if (value < 0) {
					value += P;
				}
			}

			value_ = value;
		}

		public static ModInt operator +(ModInt lhs, ModInt rhs)
		{
			lhs.value_ = (lhs.value_ + rhs.value_) % P;
			return lhs;
		}
		public static ModInt operator +(long lhs, ModInt rhs)
		{
			rhs.value_ = (lhs + rhs.value_) % P;
			return rhs;
		}
		public static ModInt operator +(ModInt lhs, long rhs)
		{
			lhs.value_ = (lhs.value_ + rhs) % P;
			return lhs;
		}

		public static ModInt operator -(ModInt lhs, ModInt rhs)
		{
			lhs.value_ = (P + lhs.value_ - rhs.value_) % P;
			return lhs;
		}
		public static ModInt operator -(long lhs, ModInt rhs)
		{
			rhs.value_ = (P + lhs - rhs.value_) % P;
			return rhs;
		}
		public static ModInt operator -(ModInt lhs, long rhs)
		{
			lhs.value_ = (P + lhs.value_ - rhs) % P;
			return lhs;
		}

		public static ModInt operator *(ModInt lhs, ModInt rhs)
		{
			lhs.value_ = lhs.value_ * rhs.value_ % P;
			return lhs;
		}
		public static ModInt operator *(long lhs, ModInt rhs)
		{
			rhs.value_ = lhs * rhs.value_ % P;
			return rhs;
		}
		public static ModInt operator *(ModInt lhs, long rhs)
		{
			lhs.value_ = lhs.value_ * rhs % P;
			return lhs;
		}

		public static ModInt operator /(ModInt lhs, ModInt rhs)
		{
			long exp = P - 2;
			while (exp > 0) {
				if (exp % 2 > 0) {
					lhs *= rhs;
				}

				rhs *= rhs;
				exp /= 2;
			}

			return lhs;
		}

		public static implicit operator ModInt(long n) => new ModInt(n, true);
		public long ToLong() => value_;
		public override string ToString() => value_.ToString();
	}

	public static class Helper
	{
		[MethodImpl(MethodImplOptions.AggressiveInlining)]
		public static void UpdateMin<T>(ref T target, T value) where T : IComparable<T>
			=> target = target.CompareTo(value) > 0 ? value : target;
		[MethodImpl(MethodImplOptions.AggressiveInlining)]
		public static void UpdateMin<T>(ref T target, T value, Action<T> onUpdated) where T : IComparable<T>
		{
			if (target.CompareTo(value) > 0) {
				target = value;
				onUpdated(value);
			}
		}

		[MethodImpl(MethodImplOptions.AggressiveInlining)]
		public static void UpdateMax<T>(ref T target, T value) where T : IComparable<T>
			=> target = target.CompareTo(value) < 0 ? value : target;
		[MethodImpl(MethodImplOptions.AggressiveInlining)]
		public static void UpdateMax<T>(ref T target, T value, Action<T> onUpdated) where T : IComparable<T>
		{
			if (target.CompareTo(value) < 0) {
				target = value;
				onUpdated(value);
			}
		}

		[MethodImpl(MethodImplOptions.AggressiveInlining)]
		public static T[] Array<T>(int n, Func<int, T> init)
			=> Enumerable.Range(0, n).Select(x => init(x)).ToArray();
		[MethodImpl(MethodImplOptions.AggressiveInlining)]
		public static List<T> List<T>(int n, Func<int, T> init)
			=> Enumerable.Range(0, n).Select(x => init(x)).ToList();

		[MethodImpl(MethodImplOptions.AggressiveInlining)]
		public static T[,] Array2<T>(int n, int m, T init)
			where T : struct
		{
			var array = new T[n, m];
			for (int i = 0; i < n; i++) {
				for (int j = 0; j < m; j++) {
					array[i, j] = init;
				}
			}

			return array;
		}
		[MethodImpl(MethodImplOptions.AggressiveInlining)]
		public static T[,] Array2<T>(int n, int m, Func<int, int, T> initializer)
		{
			var array = new T[n, m];
			for (int i = 0; i < n; i++) {
				for (int j = 0; j < m; j++) {
					array[i, j] = initializer(i, j);
				}
			}

			return array;
		}

		[MethodImpl(MethodImplOptions.AggressiveInlining)]
		public static T[,,] Array3<T>(int n1, int n2, int n3, T init)
			where T : struct
		{
			var array = new T[n1, n2, n3];
			for (int i1 = 0; i1 < n1; i1++) {
				for (int i2 = 0; i2 < n2; i2++) {
					for (int i3 = 0; i3 < n3; i3++) {
						array[i1, i2, i3] = init;
					}
				}
			}

			return array;
		}

		[MethodImpl(MethodImplOptions.AggressiveInlining)]
		public static T[,,,] Array4<T>(int n1, int n2, int n3, int n4, T init)
			where T : struct
		{
			var array = new T[n1, n2, n3, n4];
			for (int i1 = 0; i1 < n1; i1++) {
				for (int i2 = 0; i2 < n2; i2++) {
					for (int i3 = 0; i3 < n3; i3++) {
						for (int i4 = 0; i4 < n4; i4++) {
							array[i1, i2, i3, i4] = init;
						}
					}
				}
			}

			return array;
		}

		private static readonly int[] delta4_ = { 1, 0, -1, 0, 1 };
		[MethodImpl(MethodImplOptions.AggressiveInlining)]
		public static void DoAt4(int i, int j, int imax, int jmax, Action<int, int> action)
		{
			for (int dn = 0; dn < 4; dn++) {
				int d4i = i + delta4_[dn];
				int d4j = j + delta4_[dn + 1];
				if ((uint)d4i < (uint)imax && (uint)d4j < (uint)jmax) {
					action(d4i, d4j);
				}
			}
		}

		private static readonly int[] delta8_ = { 1, 0, -1, 0, 1, 1, -1, -1, 1 };
		[MethodImpl(MethodImplOptions.AggressiveInlining)]
		public static void DoAt8(int i, int j, int imax, int jmax, Action<int, int> action)
		{
			for (int dn = 0; dn < 8; dn++) {
				int d8i = i + delta8_[dn];
				int d8j = j + delta8_[dn + 1];
				if ((uint)d8i < (uint)imax && (uint)d8j < (uint)jmax) {
					action(d8i, d8j);
				}
			}
		}

		[MethodImpl(MethodImplOptions.AggressiveInlining)]
		public static void ForEachSubBit(int bit, Action<int> action)
		{
			for (int sub = bit; sub >= 0; sub--) {
				sub &= bit;
				action(sub);
			}
		}

		[MethodImpl(MethodImplOptions.AggressiveInlining)]
		public static string Reverse(string src)
		{
			var chars = src.ToCharArray();
			for (int i = 0, j = chars.Length - 1; i < j; i++, j--) {
				var tmp = chars[i];
				chars[i] = chars[j];
				chars[j] = tmp;
			}
			return new string(chars);
		}

		[MethodImpl(MethodImplOptions.AggressiveInlining)]
		public static string Join<T>(this IEnumerable<T> values, string separator = "")
			=> string.Join(separator, values);
	}

	public class Scanner : IDisposable
	{
		private const int BUFFER_SIZE = 1024;
		private const int ASCII_CHAR_BEGIN = 33;
		private const int ASCII_CHAR_END = 126;
		private readonly string filePath_;
		private readonly Stream stream_;
		private readonly byte[] buf_ = new byte[BUFFER_SIZE];
		private int length_ = 0;
		private int index_ = 0;
		private bool isEof_ = false;

		public Scanner(string file = "")
		{
			if (string.IsNullOrWhiteSpace(file)) {
				stream_ = Console.OpenStandardInput();
			} else {
				filePath_ = file;
				stream_ = new FileStream(file, FileMode.Open);
			}

			Console.SetOut(new StreamWriter(Console.OpenStandardOutput()) {
				AutoFlush = false
			});
		}

		public void Dispose()
		{
			Console.Out.Flush();
			stream_.Dispose();
		}

		[MethodImpl(MethodImplOptions.AggressiveInlining)]
		public char Char()
		{
			byte b;
			do {
				b = Read();
			} while (b < ASCII_CHAR_BEGIN || ASCII_CHAR_END < b);

			return (char)b;
		}

		[MethodImpl(MethodImplOptions.AggressiveInlining)]
		public string Next()
		{
			var sb = new StringBuilder();
			for (var b = Char(); b >= ASCII_CHAR_BEGIN && b <= ASCII_CHAR_END; b = (char)Read()) {
				sb.Append(b);
			}

			return sb.ToString();
		}

		[MethodImpl(MethodImplOptions.AggressiveInlining)]
		public int Int() => (int)Long();
		[MethodImpl(MethodImplOptions.AggressiveInlining)]
		public int Int(int offset) => Int() + offset;
		[MethodImpl(MethodImplOptions.AggressiveInlining)]
		public (int, int) Int2(int offset = 0)
			=> (Int(offset), Int(offset));
		[MethodImpl(MethodImplOptions.AggressiveInlining)]
		public (int, int, int) Int3(int offset = 0)
			=> (Int(offset), Int(offset), Int(offset));
		[MethodImpl(MethodImplOptions.AggressiveInlining)]
		public (int, int, int, int) Int4(int offset = 0)
			=> (Int(offset), Int(offset), Int(offset), Int(offset));
		[MethodImpl(MethodImplOptions.AggressiveInlining)]
		public int[] ArrayInt(int length, int offset = 0)
		{
			int[] Array = new int[length];
			for (int i = 0; i < length; i++) {
				Array[i] = Int(offset);
			}
			return Array;
		}

		[MethodImpl(MethodImplOptions.AggressiveInlining)]
		public long Long()
		{
			long ret = 0;
			byte b;
			bool ng = false;
			do {
				b = Read();
			} while (b != '-' && (b < '0' || '9' < b));

			if (b == '-') {
				ng = true;
				b = Read();
			}

			for (; true; b = Read()) {
				if (b < '0' || '9' < b) {
					return ng ? -ret : ret;
				} else {
					ret = ret * 10 + b - '0';
				}
			}
		}

		[MethodImpl(MethodImplOptions.AggressiveInlining)]
		public long Long(long offset) => Long() + offset;
		[MethodImpl(MethodImplOptions.AggressiveInlining)]
		public (long, long) Long2(long offset = 0)
			=> (Long(offset), Long(offset));
		[MethodImpl(MethodImplOptions.AggressiveInlining)]
		public (long, long, long) Long3(long offset = 0)
			=> (Long(offset), Long(offset), Long(offset));
		[MethodImpl(MethodImplOptions.AggressiveInlining)]
		public (long, long, long, long) Long4(long offset = 0)
			=> (Long(offset), Long(offset), Long(offset), Long(offset));
		[MethodImpl(MethodImplOptions.AggressiveInlining)]
		public long[] ArrayLong(int length, long offset = 0)
		{
			long[] Array = new long[length];
			for (int i = 0; i < length; i++) {
				Array[i] = Long(offset);
			}
			return Array;
		}

		[MethodImpl(MethodImplOptions.AggressiveInlining)]
		public double Double() => double.Parse(Next(), CultureInfo.InvariantCulture);
		[MethodImpl(MethodImplOptions.AggressiveInlining)]
		public double Double(double offset) => Double() + offset;
		[MethodImpl(MethodImplOptions.AggressiveInlining)]
		public (double, double) Double2(double offset = 0)
			=> (Double(offset), Double(offset));
		[MethodImpl(MethodImplOptions.AggressiveInlining)]
		public (double, double, double) Double3(double offset = 0)
			=> (Double(offset), Double(offset), Double(offset));
		[MethodImpl(MethodImplOptions.AggressiveInlining)]
		public (double, double, double, double) Double4(double offset = 0)
			=> (Double(offset), Double(offset), Double(offset), Double(offset));
		[MethodImpl(MethodImplOptions.AggressiveInlining)]
		public double[] ArrayDouble(int length, double offset = 0)
		{
			double[] Array = new double[length];
			for (int i = 0; i < length; i++) {
				Array[i] = Double(offset);
			}
			return Array;
		}

		private byte Read()
		{
			if (isEof_) {
				throw new EndOfStreamException();
			}

			if (index_ >= length_) {
				index_ = 0;
				if ((length_ = stream_.Read(buf_, 0, BUFFER_SIZE)) <= 0) {
					isEof_ = true;
					return 0;
				}
			}

			return buf_[index_++];
		}

		public void Save(string text)
		{
			if (string.IsNullOrWhiteSpace(filePath_)) {
				return;
			}

			File.WriteAllText(filePath_ + "_output.txt", text);
		}
	}
}