using System;
using System.Linq;
using System.Linq.Expressions;
using System.Collections.Generic;
using Debug = System.Diagnostics.Debug;
using StringBuilder = System.Text.StringBuilder;
using System.Numerics;
using Number = System.Int64;
namespace Program
{
    public class Solver
    {
        public void Solve()
        {
            var n = sc.Integer();
            var G = new HLTreeGraph(n);
            for (int i = 0; i < n - 1; i++)
            {
                G.AddEdge(sc.Integer() - 1, sc.Integer() - 1);
            }
            G.Build(0);
            var q = sc.Integer();
            Debug.WriteLine(q);
            long ans = 0;
            for (int i = 0; i < q; i++)
            {
                var val = G.Query(sc.Integer() - 1, sc.Integer() - 1);
                Debug.WriteLine(val);
                ans += val;
            }
            IO.Printer.Out.WriteLine(ans);
        }
        public IO.StreamScanner sc = new IO.StreamScanner(Console.OpenStandardInput());
        static T[] Enumerate<T>(int n, Func<int, T> f) { var a = new T[n]; for (int i = 0; i < n; ++i) a[i] = f(i); return a; }
        static public void Swap<T>(ref T a, ref T b) { var tmp = a; a = b; b = tmp; }


    }
}
#region main
static class Ex
{
    static public string AsString(this IEnumerable<char> ie) { return new string(System.Linq.Enumerable.ToArray(ie)); }
    static public string AsJoinedString<T>(this IEnumerable<T> 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<T>(string format, T[] source) { base.Write(format, source.OfType<object>().ToArray()); }
        public void WriteLine<T>(string format, T[] source) { base.WriteLine(format, source.OfType<object>().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 != 0 && b != '-' && (b < '0' || '9' < b));
            if (b == 0) return long.MinValue;
            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() { var s = Scan(); return s != "" ? double.Parse(s, CultureInfo.InvariantCulture) : double.NaN; }
        private T[] enumerate<T>(int n, Func<T> 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


#region HLTreeGraph

public class HLTreeGraph
{
    int N, M;
    List<Edge>[] G;
    List<Chain> H = new List<Chain>();
    int[] subTreeSize;
    int[] par;
    int[] pos;

    public int[] d;

    int[] ord;
    //chain id
    Chain[] go;
    //chain's parent
    int[] hlpar;
    public HLTreeGraph(int n)
    {
        N = n;
        G = Enumerate(n, x => new List<Edge>());
        subTreeSize = new int[n];
        pos = new int[n];
        d = new int[n];
        par = new int[n];
        go = new Chain[n];
        ord = new int[n];
    }
    public void AddEdge(int f, int t)
    {
        G[f].Add(new Edge(f, t));
        G[t].Add(new Edge(t, f));
    }
    #region impl
    public void Build(int root)
    {
        ComputeSubTreeSize(root);
        Decomposite(new Edge(-1, root), -1, 0, 0);
        return;
        M = H.Count;
        BuildHLLCA();
    }
    public void ComputeSubTreeSize(int root)
    {
        var ord = new int[N];
        par[root] = -1;
        d[root] = 0;
        var ptr = 0;
        var last = 0;
        ord[last++] = root;
        while (ptr < last)
        {
            var p = ord[ptr++];
            foreach (var to in G[p])
            {
                if (to.to != par[p])
                {
                    par[to.to] = p;
                    d[to.to] = d[p] + 1;
                    ord[last++] = to.to;
                }
            }
        }
        for (int i = N - 1; i > 0; i--)
        {
            subTreeSize[i] += 1;
            subTreeSize[par[i]] += subTreeSize[i];
        }

    }
    public void Decomposite(Edge light, int prevId, int d, int lv)
    {
        var chain = new Chain() { light = light, id = H.Count, parId = prevId, level = lv };
        H.Add(chain);
        var prev = light.from;
        var cur = light.to;
        while (cur != prev)
        {
            var next = cur;
            var max = 0;
            go[cur] = chain;
            pos[cur] = chain.heavy.Count;
            foreach (var to in G[cur])
            {
                var t = to.to;
                if (t != prev) max = Math.Max(max, subTreeSize[t]);
            }
            foreach (var to in G[cur])
            {
                var t = to.to;
                if (t == prev) continue;
                if (max == subTreeSize[t])
                {
                    //Debug.WriteLine("{0}->{1}", cur, t);
                    max = 1 << 30;
                    next = t;
                    chain.heavy.Add(to);
                }
                else Decomposite(to, chain.id, d + 1, lv + 1);
            }
            prev = cur;
            cur = next;
            d++;
        }
        chain.init(this);

    }
    const int HLHEIGHT = 8;

    void BuildHLLCA()
    {

        if (H.Max(x => x.level) > 1 << 7) throw new Exception();
        hlpar = new int[HLHEIGHT * M];
        for (int k = 0; k < HLHEIGHT; k++)
            for (int v = 0; v < M; v++)
                hlpar[k * M + v] = -1;
        for (int i = 0; i < M; i++)
            hlpar[i] = H[i].parId;
        for (int k = 1; k < HLHEIGHT; k++)
            for (int v = 0; v < M; v++)
                if (hlpar[(k - 1) * M + v] >= 0) hlpar[k * M + v] = hlpar[(k - 1) * M + hlpar[(k - 1) * M + v]];

    }
    public int GetAncestorAt(Chain v, int lv)
    {
        var id = v.id;
        var d = v.level - lv;
        for (int i = 0; i < HLHEIGHT; i++)
            if ((d >> i & 1) == 1)
                id = hlpar[i * M + id];
        return id;
    }
    public long Query(int u, int v)
    {
        long ans = 0;
        ans += d[u];
        ans += d[v];
        while (go[u].id != go[v].id)
        {
            if (go[u].level > go[v].level)
            {
                ans += go[u].seg[pos[u] + 1];
                go[u].seg.Add(1, pos[u] + 1, 1);
                u = go[u].light.from;
            }
            else
            {
                ans += go[v].seg[pos[v] + 1];
                go[v].seg.Add(1, pos[v] + 1, 1);
                v = go[v].light.from;
            }
        }
        if (pos[u] < pos[v])
            ans += -2 * d[u] + 1;
        else ans += -2 * d[v] + 1;

        var min = Math.Min(pos[u], pos[v]);
        var max = Math.Max(pos[u], pos[v]);
        ans += go[u].seg[min + 1, max + 1];
        go[u].seg.Add(min + 1, max + 1, 1);
        return ans;
    }
    public int GetLCA(int u, int v)
    {
        if (go[u].level > go[v].level) { var tmp = u; u = v; v = tmp; }
        if (go[u].level < go[v].level)
            v = H[GetAncestorAt(go[v], go[u].level + 1)].light.from;
        if (go[u].id == go[v].id)
        {
            if (d[u] <= d[v]) return u;
            else return v;
        }
        //HL
        {
            u = go[u].id;
            v = go[v].id;
            for (int i = HLHEIGHT - 1; i >= 0; i--)
            {
                if (hlpar[i * M + u] != hlpar[i * M + v])
                {
                    u = hlpar[i * M + u];
                    v = hlpar[i * M + v];
                }
            }
            for (int i = HLHEIGHT - 1; i >= 0; i--)
            {
                if (hlpar[i * M + u] != hlpar[i * M + v])
                {
                    u = hlpar[i * M + u];
                    v = hlpar[i * M + v];
                }
            }
        }
        //Tree
        {
            u = H[u].light.from;
            v = H[v].light.from;
        }

        if (d[u] <= d[v]) return u;
        else return v;
    }

    static T[] Enumerate<T>(int n, Func<int, T> f) { var a = new T[n]; for (int i = 0; i < n; ++i) a[i] = f(i); return a; }
    #endregion
}
public class Chain
{
    public Edge light;
    public List<Edge> heavy = new List<Edge>();
    public int parId;
    public int level;
    public int id;
    public RangeAddFenwickTree seg;
    public void init(HLTreeGraph G)
    {
        seg = new RangeAddFenwickTree(heavy.Count + 2);
    }
    public override string ToString()
    {
        var s = new List<int>();
        s.Add(light.from);
        s.Add(light.to);
        foreach (var e in heavy)
            s.Add(e.to);
        return s.AsJoinedString("->");
    }
}
#endregion
#region TreeEdge
public struct Edge
{
    public int from, to;
    public Edge(int f, int t)
    {
        from = f; to = t;
    }
    public override string ToString()
    {
        return string.Format("{0}->{1}", from, to);
    }
}
#endregion
#region FenwickTree
[System.Diagnostics.DebuggerDisplay("Data={ToString()}")]
public class FenwickTree
{
    int n;
    long[] bit;
    int max = 1;
    public FenwickTree(int size)
    {
        n = size; bit = new long[n + 1];
        while ((max << 1) <= n) max <<= 1;
    }
    /// <summary>sum[a,b]</summary>
    public long this[int i, int j] { get { return this[j] - this[i - 1]; } }
    /// <summary>sum[0,i]</summary>
    public long this[int i] { get { long s = 0; for (; i > 0; i -= i & -i) s += bit[i]; return s; } }
    public int LowerBound(long w)
    {
        if (w <= 0) return 0;
        int x = 0;
        for (int k = max; k > 0; k >>= 1)
            if (x + k <= n && bit[x + k] < w)
            {
                w -= bit[x + k];
                x += k;
            }
        return x + 1;
    }
    /// <summary>add v to bit[i]</summary>
    public void Add(int i, long v)
    {
        if (i == 0) System.Diagnostics.Debug.Fail("BIT is 1 indexed");
        for (; i <= n; i += i & -i) bit[i] += v;
    }
    public override string ToString() { return string.Join(",", Enumerable.Range(0, n + 1).Select(i => this[i, i])); }
}
#endregion
#region RangeAddFenwickTree
public class RangeAddFenwickTree
{
    int n;
    FenwickTree a, b;
    public RangeAddFenwickTree(int n)
    {
        this.n = n;
        a = new FenwickTree(n);
        b = new FenwickTree(n);
    }
    /// <summary>Add V to[i,j]</summary>
    public void Add(int i, int j, long v)
    {
        a.Add(i, -(i - 1) * v); a.Add(j + 1, j * v);
        b.Add(i, v); b.Add(j + 1, -v);
    }
    /// <summary>Sum [0,i]</summary>
    public long this[int i] { get { return a[i] + b[i] * i; } }
    /// <summary>Sum [i,j]</summary>
    public long this[int i, int j] { get { return this[j] - this[i - 1]; } }
    public override string ToString() { return string.Join(",", Enumerable.Range(0, n + 1).Select(i => this[i, i])); }

}
#endregion