n, k = map(int, input().split())
g: list[list[tuple[int, int, int]]] = [[] for _ in range(n)]
for eid in range(n - 1):
    u, v, c = map(int, input().split())
    u -= 1
    v -= 1
    g[u].append((c, eid, v))
    g[v].append((c, eid, u))

uf = [-1] * (n - 1)


def size(x: int) -> int:
    return -uf[find(x)]


def find(x: int) -> int:
    if uf[x] < 0:
        return x
    uf[x] = find(uf[x])
    return uf[x]


def merge(x: int, y: int) -> None:
    x = find(x)
    y = find(y)
    if x == y:
        return
    if uf[x] > uf[y]:
        x, y = y, x
    uf[x] += uf[y]
    uf[y] = x


for i in range(n):
    g[i].sort()
    siz = len(g[i])
    for j in range(siz - 1):
        c1, eid1, v1 = g[i][j]
        c2, eid2, v2 = g[i][j + 1]
        if c1 == c2:
            merge(eid1, eid2)

ans = 0
for i in range(n):
    siz = len(g[i])
    cmps: list[int] = []
    for j in range(siz):
        if j == 0 or g[i][j][0] != g[i][j - 1][0]:
            cmps.append(size(g[i][j][1]))
    ans += (sum(cmps) ** 2 - sum(e ** 2 for e in cmps)) // 2
print(ans)