n,K=map(int,input().split())
e=[[] for i in range(n)]
for _ in range(n-1):
  a,b,c=map(int,input().split())
  a-=1
  b-=1
  c-=1
  e[a]+=[(b,c)]
  e[b]+=[(a,c)]

cdc=[]
cdp=[-1]*n
v=[0]*n
u=[0]*n
cdq=[0]
for start in cdq:
  q=[start]
  while len(q)>0:
    s=q[-1]
    if v[s]==0:
      v[s]=1
      q+=[t for t,_ in e[s] if v[t]==0 and cdp[t]==-1]
    else:
      u[s]=1+sum([u[t] for t,_ in e[s] if v[t]==0 and cdp[t]==-1])
      v[s]=0
      q.pop()
  q=[start]
  while len(q)>0:
    s=q[-1]
    if v[s]==0:
      if all((u[t] if v[t]==0 else u[start]-u[s])<=u[start]//2 or cdp[t]!=-1 for t,_ in e[s]):
        o=s
      v[s]=1
      q+=[t for t,_ in e[s] if v[t]==0 and cdp[t]==-1]
    else:
      v[s]=0
      q.pop()
  cdp[o]=len(cdc)
  cdc+=[o]
  cdq+=[t for t,_ in e[o] if cdp[t]==-1]

ans=0

v=[0]*n
st1=[{} for i in range(n)]
st2=[{} for i in range(n)]
st3=[0]*K
st4={}
st5=[0]*n
st6=[0]*K
uc=[0]*K
for C in cdc[::-1]:
  st4={}
  u=set()
  for root,c in e[C]:
    if cdp[root]>cdp[C]:
      st1[root]={}
      st2[root]={}
      q=[(root,c)]
      while len(q)>0:
        s,sc=q[-1]
        if v[s]==0:
          v[s]=1
          uc[sc]+=1
          if uc[sc]==1:
            u.add(sc)
          if len(u)==1:
            c1=sorted(u)[0]
            if c1 not in st1[root]:
              st1[root][c1]=0
            st1[root][c1]+=1
            st3[c1]+=1
            st5[C]+=1
          if len(u)==2:
            c1,c2=sorted(u)
            c1c2=c1*K+c2
            if c1c2 not in st2[root]:
              st2[root][c1c2]=0
            st2[root][c1c2]+=1
            if c1c2 not in st4:
              st4[c1c2]=0
            st4[c1c2]+=1
            st6[c1]+=1
            st6[c2]+=1
          for t,tc in e[s]:
            if v[t]==0 and cdp[t]>cdp[C]:
              q+=[(t,tc)]
        else:
          v[s]=0
          uc[sc]-=1
          if uc[sc]==0:
            u.remove(sc)
          q.pop()
  ans+=sum(st4[c1c2] for c1c2 in st4)*2
  u=set()
  for root,c in e[C]:
    if cdp[root]>cdp[C]:
      for c1 in st1[root]:
        x=st1[root][c1]
        st3[c1]-=x
        st5[C]-=x
      for c1c2 in st2[root]:
        x=st2[root][c1c2]
        st4[c1c2]-=x
        st6[c1c2//K]-=x
        st6[c1c2%K]-=x
      q=[(root,c)]
      while len(q)>0:
        s,sc=q[-1]
        if v[s]==0:
          v[s]=1
          uc[sc]+=1
          if uc[sc]==1:
            u.add(sc)
          if len(u)==1:
            c1=sorted(u)[0]
            ans+=st5[C]-st3[c1]
            ans+=st6[c1]*2
          if len(u)==2:
            c1,c2=sorted(u)
            c1c2=c1*K+c2
            ans+=st4[c1c2]
          for t,tc in e[s]:
            if v[t]==0 and cdp[t]>cdp[C]:
              q+=[(t,tc)]
        else:
          v[s]=0
          uc[sc]-=1
          if uc[sc]==0:
            u.remove(sc)
          q.pop()
      for c1 in st1[root]:
        x=st1[root][c1]
        st3[c1]+=x
        st5[C]+=x
      for c1c2 in st2[root]:
        x=st2[root][c1c2]
        st4[c1c2]+=x
        st6[c1c2//K]+=x
        st6[c1c2%K]+=x
  u=set()
  for root,c in e[C]:
    if cdp[root]>cdp[C]:
      q=[(root,c)]
      while len(q)>0:
        s,sc=q[-1]
        if v[s]==0:
          v[s]=1
          uc[sc]+=1
          if uc[sc]==1:
            u.add(sc)
          if len(u)==1:
            c1=sorted(u)[0]
            st3[c1]-=1
            st5[C]-=1
          if len(u)==2:
            c1,c2=sorted(u)
            c1c2=c1*K+c2
            st6[c1]-=1
            st6[c2]-=1
          for t,tc in e[s]:
            if v[t]==0 and cdp[t]>cdp[C]:
              q+=[(t,tc)]
        else:
          v[s]=0
          uc[sc]-=1
          if uc[sc]==0:
            u.remove(sc)
          q.pop()

print(ans//2)