package main

import (
	"bufio"
	"os"
	"sort"
)

type FastScanner struct {
	r        *os.File
	buf      []byte
	idx, n   int
}

func NewFastScanner() *FastScanner {
	return &FastScanner{
		r:   os.Stdin,
		buf: make([]byte, 1<<20),
	}
}

func (fs *FastScanner) refill() bool {
	n, _ := fs.r.Read(fs.buf)
	fs.idx = 0
	fs.n = n
	return n > 0
}

func (fs *FastScanner) NextInt() int {
	sign := 1
	val := 0
	for {
		if fs.idx >= fs.n {
			if !fs.refill() {
				return 0
			}
		}
		c := fs.buf[fs.idx]
		if (c >= '0' && c <= '9') || c == '-' {
			if c == '-' {
				sign = -1
				fs.idx++
			}
			break
		}
		fs.idx++
	}
	for {
		if fs.idx >= fs.n {
			if !fs.refill() {
				break
			}
		}
		c := fs.buf[fs.idx]
		if c < '0' || c > '9' {
			break
		}
		val = val*10 + int(c-'0')
		fs.idx++
	}
	return sign * val
}

type Edge struct {
	u, v, w, id int32
}

type ByWeight []Edge

func (a ByWeight) Len() int           { return len(a) }
func (a ByWeight) Less(i, j int) bool { return a[i].w < a[j].w }
func (a ByWeight) Swap(i, j int)      { a[i], a[j] = a[j], a[i] }

func find(parent []int32, x int32) int32 {
	for parent[int(x)] != x {
		parent[int(x)] = parent[int(parent[int(x)])]
		x = parent[int(x)]
	}
	return x
}

func union(parent, size []int32, a, b int32) bool {
	ra := find(parent, a)
	rb := find(parent, b)
	if ra == rb {
		return false
	}
	if size[int(ra)] < size[int(rb)] {
		ra, rb = rb, ra
	}
	parent[int(rb)] = ra
	size[int(ra)] += size[int(rb)]
	return true
}

func query(u, v int32, up, mx [][]int32, depth []int, kmax int) int32 {
	var res int32
	if depth[int(u)] < depth[int(v)] {
		u, v = v, u
	}
	diff := depth[int(u)] - depth[int(v)]
	k := 0
	for diff > 0 {
		if diff&1 == 1 {
			t := mx[k][int(u)]
			if t > res {
				res = t
			}
			u = up[k][int(u)]
		}
		diff >>= 1
		k++
	}
	if u == v {
		return res
	}
	for k = kmax - 1; k >= 0; k-- {
		pu := up[k][int(u)]
		pv := up[k][int(v)]
		if pu != pv {
			t := mx[k][int(u)]
			if t > res {
				res = t
			}
			t = mx[k][int(v)]
			if t > res {
				res = t
			}
			u = pu
			v = pv
		}
	}
	t := mx[0][int(u)]
	if t > res {
		res = t
	}
	t = mx[0][int(v)]
	if t > res {
		res = t
	}
	return res
}

func appendInt32(buf []byte, x int32) []byte {
	if x == 0 {
		return append(buf, '0')
	}
	var tmp [11]byte
	i := len(tmp)
	for x > 0 {
		i--
		tmp[i] = byte(x%10) + '0'
		x /= 10
	}
	return append(buf, tmp[i:]...)
}

func main() {
	fs := NewFastScanner()
	n := fs.NextInt()
	m := fs.NextInt()

	edges := make([]Edge, m)
	for i := 0; i < m; i++ {
		u := fs.NextInt()
		v := fs.NextInt()
		w := fs.NextInt()
		edges[i] = Edge{int32(u), int32(v), int32(w), int32(i)}
	}

	sort.Sort(ByWeight(edges))

	parent := make([]int32, n+1)
	size := make([]int32, n+1)
	for i := 1; i <= n; i++ {
		parent[i] = int32(i)
		size[i] = 1
	}

	isMST := make([]bool, m)

	head := make([]int32, n+1)
	for i := 1; i <= n; i++ {
		head[i] = -1
	}
	to := make([]int32, 2*(n-1))
	wt := make([]int32, 2*(n-1))
	next := make([]int32, 2*(n-1))
	var ec int32

	addEdge := func(u, v, w int32) {
		to[int(ec)] = v
		wt[int(ec)] = w
		next[int(ec)] = head[int(u)]
		head[int(u)] = ec
		ec++
	}

	added := 0
	for i := 0; i < m && added < n-1; i++ {
		e := edges[i]
		if union(parent, size, e.u, e.v) {
			isMST[int(e.id)] = true
			addEdge(e.u, e.v, e.w)
			addEdge(e.v, e.u, e.w)
			added++
		}
	}

	kmax := 0
	for (1 << kmax) <= n {
		kmax++
	}

	up := make([][]int32, kmax)
	mx := make([][]int32, kmax)
	for i := 0; i < kmax; i++ {
		up[i] = make([]int32, n+1)
		mx[i] = make([]int32, n+1)
	}

	depth := make([]int, n+1)
	queue := make([]int32, n)
	queue[0] = 1
	qh, qt := 0, 1

	for qh < qt {
		u := queue[qh]
		qh++
		pu := up[0][int(u)]
		for ei := head[int(u)]; ei != -1; ei = next[int(ei)] {
			v := to[int(ei)]
			if v == pu {
				continue
			}
			up[0][int(v)] = u
			mx[0][int(v)] = wt[int(ei)]
			depth[int(v)] = depth[int(u)] + 1
			queue[qt] = v
			qt++
		}
	}

	for k := 1; k < kmax; k++ {
		upPrev := up[k-1]
		mxPrev := mx[k-1]
		upCur := up[k]
		mxCur := mx[k]
		for v := 1; v <= n; v++ {
			p := upPrev[v]
			upCur[v] = upPrev[int(p)]
			a := mxPrev[v]
			b := mxPrev[int(p)]
			if b > a {
				a = b
			}
			mxCur[v] = a
		}
	}

	ans := make([]int32, m)
	for i := 0; i < m; i++ {
		id := int(edges[i].id)
		if !isMST[id] {
			ans[id] = query(edges[i].u, edges[i].v, up, mx, depth, kmax)
		}
	}

	out := make([]byte, 0, (m-n+1)*12)
	for i := 0; i < m; i++ {
		if !isMST[i] {
			out = appendInt32(out, ans[i])
			out = append(out, '\n')
		}
	}

	w := bufio.NewWriterSize(os.Stdout, 1<<20)
	w.Write(out)
	w.Flush()
}