using System; using System.Linq; using System.Diagnostics; using System.Collections.Generic; using Debug = System.Diagnostics.Debug; using StringBuilder = System.Text.StringBuilder; using System.Numerics; namespace Program { public class Solver { public void Solve() { var s = sc.Scan(); var t = sc.Scan(); var n = s.Length; var m = t.Length; var pt = new PalindromicTree((s + "${" + t).ToCharArray(), n); long ret = 0; for (int i = 2; i < pt.nodes.Length; i++) { if (pt.nodes[i] != null) ret += (long)pt.nodes[i].freq0 * pt.nodes[i].freq1; } IO.Printer.Out.WriteLine(ret); } public IO.StreamScanner sc = new IO.StreamScanner(Console.OpenStandardInput()); static T[] Enumerate(int n, Func f) { var a = new T[n]; for (int i = 0; i < n; ++i) a[i] = f(i); return a; } static public void Swap(ref T a, ref T b) { var tmp = a; a = b; b = tmp; } } } #region main static class Ex { static public string AsString(this IEnumerable ie) { return new string(System.Linq.Enumerable.ToArray(ie)); } static public string AsJoinedString(this IEnumerable ie, string st = " ") { return string.Join(st, ie); } static public void Main() { var solver = new Program.Solver(); solver.Solve(); Program.IO.Printer.Out.Flush(); } } #endregion #region Ex namespace Program.IO { using System.IO; using System.Text; using System.Globalization; public class Printer : StreamWriter { static Printer() { Out = new Printer(Console.OpenStandardOutput()) { AutoFlush = false }; } public static Printer Out { get; set; } public override IFormatProvider FormatProvider { get { return CultureInfo.InvariantCulture; } } public Printer(System.IO.Stream stream) : base(stream, new UTF8Encoding(false, true)) { } public Printer(System.IO.Stream stream, Encoding encoding) : base(stream, encoding) { } public void Write(string format, T[] source) { base.Write(format, source.OfType().ToArray()); } public void WriteLine(string format, T[] source) { base.WriteLine(format, source.OfType().ToArray()); } } public class StreamScanner { public StreamScanner(Stream stream) { str = stream; } public readonly Stream str; private readonly byte[] buf = new byte[1024]; private int len, ptr; public bool isEof = false; public bool IsEndOfStream { get { return isEof; } } private byte read() { if (isEof) return 0; if (ptr >= len) { ptr = 0; if ((len = str.Read(buf, 0, 1024)) <= 0) { isEof = true; return 0; } } return buf[ptr++]; } public char Char() { byte b = 0; do b = read(); while ((b < 33 || 126 < b) && !isEof); return (char)b; } public string Scan() { var sb = new StringBuilder(); for (var b = Char(); b >= 33 && b <= 126; b = (char)read()) sb.Append(b); return sb.ToString(); } public string ScanLine() { var sb = new StringBuilder(); for (var b = Char(); b != '\n'; b = (char)read()) if (b == 0) break; else if (b != '\r') sb.Append(b); return sb.ToString(); } public long Long() { if (isEof) return long.MinValue; long ret = 0; byte b = 0; var 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'; } } public int Integer() { return (isEof) ? int.MinValue : (int)Long(); } public double Double() { return double.Parse(Scan(), CultureInfo.InvariantCulture); } private T[] enumerate(int n, Func f) { var a = new T[n]; for (int i = 0; i < n; ++i) a[i] = f(); return a; } public char[] Char(int n) { return enumerate(n, Char); } public string[] Scan(int n) { return enumerate(n, Scan); } public double[] Double(int n) { return enumerate(n, Double); } public int[] Integer(int n) { return enumerate(n, Integer); } public long[] Long(int n) { return enumerate(n, Long); } } } #endregion public class PalindromicTree { public Node[] nodes; public int N; public PalindromicTree(char[] s, int nn) { N = nn; var n = s.Length; var zero = new Node(-1, 0, (char)0, 1); var hell = new Node(-1, -1, (char)0, 0); zero.link = hell.link = hell; hell.Add(zero); nodes = new Node[n + 2]; var ptr = 0; nodes[ptr++] = hell; nodes[ptr++] = zero; var cur = zero;//current suffix for (int i = 0; i < n; i++) { var x = s[i]; while (i - cur.len - 1 < 0 || s[i - cur.len - 1] != x) cur = cur.link;//find xAx var xax = cur.Next(x);//already exists if (xax == null) { //new subpalindrome xax = new Node(i - cur.len - 1, cur.len + 2, x, ptr); nodes[ptr++] = xax; cur.Add(xax); //make suffix link if (xax.len == 1) xax.link = zero; else { var b = cur.link; while (true) { while (i - b.len < 0 || s[i - b.len - 1] != x) b = b.link;//find xBx var xbx = b.Next(x); if (xbx != null) { xax.link = xbx; break; } } } } if (i < nn) xax.freq0++; else if (i - xax.len + 1 >= nn + 2) xax.freq1++; cur = xax; } for (int i = ptr - 1; i >= 2; i--) { nodes[i].link.freq0 += nodes[i].freq0; nodes[i].link.freq1 += nodes[i].freq1; } } public class Node { public int id, first, len, freq0, freq1; public char c; public Node firstChild; public Node sibling; public Node link; public Node(int first, int len, char c, int id) { this.first = first; this.len = len; this.c = c; this.id = id; this.freq0 = this.freq1 = 0; } public Node Next(char c) { for (Node ch = firstChild; ch != null; ch = ch.sibling) if (ch.c == c) return ch; return null; } public void Add(Node x) { var ch = firstChild; firstChild = x; x.sibling = ch; } public override string ToString() { return string.Format("Node [id={0}, first={1}, len={2}, freq0={3}, freq1={4}, c={5}, firstchild={6}, sibling={7}, link={8}]", id, first, len, freq0, freq1, c, firstChild != null ? firstChild.id : -1, sibling != null ? sibling.id : -1, link != null ? link.id : -1); } } }