using System;
using System.Linq;
using System.Collections.Generic;
using Debug = System.Diagnostics.Debug;
using SB = System.Text.StringBuilder;
using System.Numerics;
using static System.Math;
using Number = System.UInt32;
namespace Program {
    public class Solver {
        Random rnd = new Random(0);
        public void Solve() {
            var n = ri; var m = ri;
            var X = Enumerate(n, x => rl);
            var A = new int[m];
            var B = new int[m];
            var Y = new long[m];
            for (int i = 0; i < m; i++) {
                A[i] = ri - 1;
                B[i] = ri - 1;
                Y[i] = rl;
            }
            var s = new DisjointSet(n, X);
            var id = Enumerate(m, x => x).OrderBy(x => Y[x]).ToArray();
            var used = new bool[m];
            foreach (var e in id) {
                if (s.Unite(A[e], B[e])) {
                    used[e] = true;
                }
            }
            foreach (var e in id.Reverse()) {
                var u = s.Size(A[e]);
                var v = s.Size(B[e]);
                Debug.WriteLine(e);
                if (used[e]) {
                    if (Y[e] > u) s.back();
                    else s.pass();
                }
                else {
                    if (!s.IsUnited(A[e], B[e]) && Y[e] <= u + v) {
                        s.Unite(A[e], B[e]);
                        s.pass();
                    }
                }
            }
            var cnt = 0;
            foreach (var e in id) {
                var u = s.Size(A[e]);
                var y = Y[e];
                if (u >= y) cnt++;
            }
            Console.WriteLine(m - cnt);

        }
        const long INF = 1L << 60;
        int ri { get { return sc.Integer(); } }
        long rl { get { return sc.Long(); } }
        double rd { get { return sc.Double(); } }
        string rs { get { return sc.Scan(); } }
        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(ie.ToArray()); }
    static public string AsJoinedString<T>(this IEnumerable<T> ie, string st = " ") {
        return string.Join(st, ie);
    }
    static public void Main() {
        Console.SetOut(new Program.IO.Printer(Console.OpenStandardOutput()) { AutoFlush = false });
        var solver = new Program.Solver();
        solver.Solve();
        Console.Out.Flush();
    }
}
#endregion
#region Ex
namespace Program.IO {
    using System.IO;
    using System.Text;
    using System.Globalization;

    public class Printer: StreamWriter {
        public override IFormatProvider FormatProvider { get { return CultureInfo.InvariantCulture; } }
        public Printer(Stream stream) : base(stream, new UTF8Encoding(false, true)) { }
    }

    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 != 0; b = (char)read()) if (b != '\r') sb.Append(b);
            return sb.ToString();
        }
        public long Long() { return isEof ? long.MinValue : long.Parse(Scan()); }
        public int Integer() { return isEof ? int.MinValue : int.Parse(Scan()); }
        public double Double() { return isEof ? double.NaN : double.Parse(Scan(), CultureInfo.InvariantCulture); }
    }
}

#endregion


#region DisjointSet
public class DisjointSet {
    long[] par;
    byte[] rank;
    Stack<KeyValuePair<int, long>> a = new Stack<KeyValuePair<int, long>>();
    public DisjointSet(int n, long[] a) {
        par = new long[n];
        for (int i = 0; i < n; i++)
            par[i] = -a[i];
        rank = new byte[n];
    }
    public int this[int id] {
        get {
            if ((par[id] < 0)) return id;
            return this[(int)par[id]];
        }
    }
    public bool Unite(int x, int y) {
        x = this[x]; y = this[y];
        if (x == y) return false;
        if (rank[x] < rank[y]) { var z = x; x = y; y = z; }
        a.Push(new KeyValuePair<int, long>(x, par[x]));
        a.Push(new KeyValuePair<int, long>(y, par[y]));
        par[x] += par[y];
        par[y] = x;
        if (rank[x] == rank[y])
            rank[x]++;
        return true;
    }
    public void back() {
        for (int k = 0; k < 2; k++) {
            var kv = a.Pop();
            par[kv.Key] = kv.Value;
        }
    }
    public void pass() {
        a.Pop(); a.Pop();
    }
    public long Size(int x) { return -par[this[x]]; }
    public bool IsUnited(int x, int y) { return this[x] == this[y]; }

}
#endregion

Measured memory_bytes: 31916