Problem:


Score : 600 points

Problem Statement

There is a tree with N vertices numbered 1 to N.
The i-th edge in this tree connects Vertex a_i and Vertex b_i, and the color and length of that edge are c_i and d_i, respectively.
Here the color of each edge is represented by an integer between 1 and N-1 (inclusive). The same integer corresponds to the same color, and different integers correspond to different colors.

Answer the following Q queries:

Query j (1 \leq j \leq Q): assuming that the length of every edge whose color is x_j is changed to y_j, find the distance between Vertex u_j and Vertex v_j. (The changes of the lengths of edges do not affect the subsequent queries.)

Constraints

2 \leq N \leq 10^5

1 \leq Q \leq 10^5

1 \leq a_i, b_i \leq N

1 \leq c_i \leq N-1

1 \leq d_i \leq 10^4

1 \leq x_j \leq N-1

1 \leq y_j \leq 10^4

1 \leq u_j < v_j \leq N

The given graph is a tree.

All values in input are integers.

Input

Input is given from Standard Input in the following format:

N Q
a_1 b_1 c_1 d_1
:
a_{N-1} b_{N-1} c_{N-1} d_{N-1}
x_1 y_1 u_1 v_1
:
x_Q y_Q u_Q v_Q

Output

Print Q lines. The j-th line (1 \leq j \leq Q) should contain the answer to Query j.

Sample Input 1

5 3
1 2 1 10
1 3 2 20
2 4 4 30
5 2 1 40
1 100 1 4
1 100 1 5
3 1000 3 4

Sample Output 1

130
200
60

The graph in this input is as follows:

Here the edges of Color 1 are shown as solid red lines, the edge of Color 2 is shown as a bold green line, and the edge of Color 4 is shown as a blue dashed line.

Query 1: Assuming that the length of every edge whose color is 1 is changed to 100, the distance between Vertex 1 and Vertex 4 is 100 + 30 = 130.

Query 2: Assuming that the length of every edge whose color is 1 is changed to 100, the distance between Vertex 1 and Vertex 5 is 100 + 100 = 200.

Query 3: Assuming that the length of every edge whose color is 3 is changed to 1000 (there is no such edge), the distance between Vertex 3 and Vertex 4 is 20 + 10 + 30 = 60. Note that the edges of Color 1 now have their original lengths.



Sample input:
5 3
1 2 1 10
1 3 2 20
2 4 4 30
5 2 1 40
1 100 1 4
1 100 1 5
3 1000 3 4


Sample output:
130
200
60

Submission status: Time Limit Exceeded

Solution code:
import sys,bisect,string,math,time,functools,random
from heapq import heappush,heappop,heapify
from collections import deque,defaultdict,Counter
from itertools import permutations,combinations,groupby
def Golf():*a,=map(int,open(0))
def I():return int(input())
def S_():return input()
def IS():return input().split()
def LS():return [i for i in input().split()]
def LI():return [int(i) for i in input().split()]
def LI_():return [int(i)-1 for i in input().split()]
def NI(n):return [int(input()) for i in range(n)]
def NI_(n):return [int(input())-1 for i in range(n)]
def StoLI():return [ord(i)-97 for i in input()]
def ItoS(n):return chr(n+97)
def LtoS(ls):return ''.join([chr(i+97) for i in ls])
def GI(V,E,ls=None,Directed=False,index=1):
    org_inp=[];g=[[] for i in range(V)]
    FromStdin=True if ls==None else False
    for i in range(E):
        if FromStdin:
            inp=LI()
            org_inp.append(inp)
        else:
            inp=ls[i]
        if len(inp)==2:
            a,b=inp;c=1
        else:
            a,b,c=inp
        if index==1:a-=1;b-=1
        aa=(a,c);bb=(b,c);g[a].append(bb)
        if not Directed:g[b].append(aa)
    return g,org_inp
def GGI(h,w,search=None,replacement_of_found='.',mp_def={'#':1,'.':0},boundary=1):
#h,w,g,sg=GGI(h,w,search=['S','G'],replacement_of_found='.',mp_def={'#':1,'.':0}) # sample usage
    mp=[boundary]*(w+2);found={}
    for i in range(h):
        s=input()
        for char in search:
            if char in s:
                found[char]=((i+1)*(w+2)+s.index(char)+1)
                mp_def[char]=mp_def[replacement_of_found]
        mp+=[boundary]+[mp_def[j] for j in s]+[boundary]
    mp+=[boundary]*(w+2)
    return h+2,w+2,mp,found
def TI(n):return GI(n,n-1)
def bit_combination(k,n=2):
    rt=[]
    for tb in range(n**k):
        s=[tb//(n**bt)%n for bt in range(k)];rt+=[s]
    return rt
def show(*inp,end='\n'):
    if show_flg:print(*inp,end=end)

YN=['YES','NO'];Yn=['Yes','No']
mo=10**9+7
inf=float('inf')
l_alp=string.ascii_lowercase
#sys.setrecursionlimit(10**7)
input=lambda: sys.stdin.readline().rstrip()

class Tree:
    def __init__(self,inp_size=None,init=True):
        self.LCA_init_stat=False
        if init:
            self.stdin(inp_size)
        return

    def stdin(self,inp_size=None,index=1):
        if inp_size==None:
            self.size=int(input())
        else:
            self.size=inp_size
        self.edges,_=GI(self.size,self.size-1,index=index)
        return
    
    def listin(self,ls,index=0):
        self.size=len(ls)+1
        self.edges,_=GI(self.size,self.size-1,ls,index=index)
        return

    def __str__(self):
        return  str(self.edges)

    def dfs(self,x,func=lambda prv,nx,dist:prv+dist,root_v=0):
        q=deque()
        q.append(x)
        v=[-1]*self.size
        v[x]=root_v
        while q:
            c=q.pop()
            for nb,d in self.edges[c]:
                if v[nb]==-1:
                    q.append(nb)
                    v[nb]=func(v[c],nb,d)
        return v

    def EulerTour(self,x,func=lambda prv,nx,dist:prv+1,root_v=0):
        q=deque()
        q.append((-1,x))
        depth=[None]*self.size
        depth[x]=root_v
        et=[]
        while q:
            cb,ce=q.pop()
            et.append(ce)
            for nb,d in self.edges[ce]:
                if depth[nb]==None:
                    q.append((nb,ce))
                    q.append((ce,nb))
                    depth[nb]=func(depth[ce],nb,d)
        vid=[[-1,-1]for i in range(self.size)]
        for i,j in enumerate(et):
            if vid[j][0]==-1:
                vid[j][0]=i
            else:
                vid[j][1]=i
        self.ETtable=et[:]
        self.ETdepth=[depth[i] for i in et]
        self.ETid=vid[:]
        return depth,et,vid

    def FastEulerTour(self,x,func=lambda prv,nx,dist:prv+1,root_v=0):
        q=deque()
        q.append(x)
        depth=[None]*self.size
        depth[x]=root_v
        et=[]
        while q:
            c=q.pop()
            if c<0:
                ce=~c
            else:
                ce=c
            et.append(ce)
            #cb,ce=q.pop()
            #et.append(ce)
            for nb,d in self.edges[ce]:
                if depth[nb]==None:
                    q.append(~ce)
                    q.append(nb)
                    #q.append((nb,ce))
                    #q.append((ce,nb))
                    depth[nb]=func(depth[ce],nb,d)
        vid=[[-1,-1]for i in range(self.size)]
        for i,j in enumerate(et):
            if vid[j][0]==-1:
                vid[j][0]=i
            else:
                vid[j][1]=i
        self.ETtable=et[:]
        self.ETdepth=[depth[i] for i in et]
        self.ETid=vid[:]
        return depth,et,vid
    
    def LCA_init(self,root):
        self.EulerTour(root,func=lambda prv,nx,dist:prv+dist,root_v=0)
        self.st=SparseTable(self.ETdepth,init_func=min,init_idl=inf)
        self.LCA_init_stat=True
        return
    
    def LCA(self,root,x,y):
        if self.LCA_init_stat==False:
            self.LCA_init(root)
        xin,xout=self.ETid[x]
        yin,yout=self.ETid[y]
        a=min(xin,yin)
        b=max(xout,yout,xin,yin)
        id_of_min_dep_in_et=self.st.query_id(a,b+1)
        #show((xin,xout),(yin,yout),(a,b),id_of_min_dep_in_et)
        return self.ETtable[id_of_min_dep_in_et]

class SparseTable: # O(N log N) for init, O(1) for query(l,r)
    def __init__(self,ls,init_func=min,init_idl=float('inf')):
        self.func=init_func
        self.idl=init_idl
        self.size=len(ls)
        self.N0=self.size.bit_length()
        self.table=[ls[:]]
        self.index=[list(range(self.size))]
        self.lg=[0]*(self.size+1)
        
        for i in range(2,self.size+1):
            self.lg[i]=self.lg[i>>1]+1

        for i in range(self.N0):
            tmp=[self.func(self.table[i][j],self.table[i][min(j+(1<<i),self.size-1)]) for j in range(self.size)]
            tmp_id=[self.index[i][j] if self.table[i][j]==self.func(self.table[i][j],self.table[i][min(j+(1<<i),self.size-1)]) else self.index[i][min(j+(1<<i),self.size-1)] for j in range(self.size)]
            self.table+=[tmp]
            self.index+=[tmp_id]
    
    # return func of [l,r)
    def query(self,l,r):
        #N=(r-l).bit_length()-1
        N=self.lg[r-l]
        return self.func(self.table[N][l],self.table[N][r-(1<<N)])
    
    # return index of which val[i] = func of v among [l,r)
    def query_id(self,l,r):
        #N=(r-l).bit_length()-1
        N=self.lg[r-l]
        a,b=self.index[N][l],self.index[N][r-(1<<N)]
        if self.table[0][a]==self.func(self.table[N][l],self.table[N][r-(1<<N)]):
            b=a
        return b
    
    def __str__(self):
        return str(self.table[0])
        
    def print(self):
        for i in self.table:
            print(*i)

show_flg=False
show_flg=True
ans=0


n,q=LI()
ls=[]
col=dict()
e_len=dict()
for i in range(n-1):
    a,b,c,d=LI_()
    d+=1
    ls+=[(a,b,d)]
    if a>b:
        a,b=b,a
    col[a*n+b]=c
    e_len[a*n+b]=d

tr=Tree(init=False)
tr.listin(ls,index=0)

root=0
dist=tr.dfs(root,func=lambda prv_v,nx,dist:prv_v+dist)
dep,et,vid=tr.FastEulerTour(root)

ad=[[0] for i in range(n)]
an=[[0] for i in range(n)]
index=[[] for i in range(n)]
for i in range(2*n-1-1):
    a,b=et[i],et[i+1]
    if a<0:a=~a
    if b<0:b=~b
    sign=1 if dep[a]<dep[b] else -1
    if a>b:
        a,b=b,a
    c=col[a*n+b]
    dd=e_len[a*n+b]*sign
    an[c]+=[an[c][-1]+sign]
    ad[c]+=[ad[c][-1]+dd]
    index[c]+=[i]
    

for i in range(q):
    x,y,u,v=LI_()
    y+=1
    ls+=[(a,b,d)]
    lca=tr.LCA(root,u,v)
    dist_u=dist[u]-dist[lca]
    dist_v=dist[v]-dist[lca]
    path=dist_u+dist_v
    
    ui=bisect.bisect_left(index[x],vid[u][0])
    vi=bisect.bisect_left(index[x],vid[v][0])
    #show(vi,bisect.bisect(index[x],vid[v][0]),(index[x],vid[v][0]))
    ai=bisect.bisect_left(index[x],vid[lca][0])
    ui=min(ui,len(index[x]))
    vi=min(vi,len(index[x]))
    ai=min(ai,len(index[x]))
    
    
    c_dist_u=ad[x][ui]-ad[x][ai]
    c_dist_v=ad[x][vi]-ad[x][ai]
    c_path=c_dist_u+c_dist_v
    c_n_u=an[x][ui]-an[x][ai]
    c_n_v=an[x][vi]-an[x][ai]
    c_n=c_n_u+c_n_v
    #ri=bisect.bisect_right(index[x],r)
    ans=path-c_path+c_n*y
    #show(ans,'col',x,(lca,(u,v)),path,(vid[lca][0],(vid[u][0],vid[v][0])),(ai,(ui,vi)),c_path,(c_dist_u,c_dist_v),index[x],'# c_path',(c_n_u,c_n_v))
    
    print(ans)

Submission status: Time Limit Exceeded

Solution code:
import sys,bisect,string,math,time,functools,random
from heapq import heappush,heappop,heapify
from collections import deque,defaultdict,Counter
from itertools import permutations,combinations,groupby
def Golf():*a,=map(int,open(0))
def I():return int(input())
def S_():return input()
def IS():return input().split()
def LS():return [i for i in input().split()]
def LI():return [int(i) for i in input().split()]
def LI_():return [int(i)-1 for i in input().split()]
def NI(n):return [int(input()) for i in range(n)]
def NI_(n):return [int(input())-1 for i in range(n)]
def StoLI():return [ord(i)-97 for i in input()]
def ItoS(n):return chr(n+97)
def LtoS(ls):return ''.join([chr(i+97) for i in ls])
def GI(V,E,ls=None,Directed=False,index=1):
    org_inp=[];g=[[] for i in range(V)]
    FromStdin=True if ls==None else False
    for i in range(E):
        if FromStdin:
            inp=LI()
            org_inp.append(inp)
        else:
            inp=ls[i]
        if len(inp)==2:
            a,b=inp;c=1
        else:
            a,b,c=inp
        if index==1:a-=1;b-=1
        aa=(a,c);bb=(b,c);g[a].append(bb)
        if not Directed:g[b].append(aa)
    return g,org_inp
def GGI(h,w,search=None,replacement_of_found='.',mp_def={'#':1,'.':0},boundary=1):
#h,w,g,sg=GGI(h,w,search=['S','G'],replacement_of_found='.',mp_def={'#':1,'.':0}) # sample usage
    mp=[boundary]*(w+2);found={}
    for i in range(h):
        s=input()
        for char in search:
            if char in s:
                found[char]=((i+1)*(w+2)+s.index(char)+1)
                mp_def[char]=mp_def[replacement_of_found]
        mp+=[boundary]+[mp_def[j] for j in s]+[boundary]
    mp+=[boundary]*(w+2)
    return h+2,w+2,mp,found
def TI(n):return GI(n,n-1)
def bit_combination(k,n=2):
    rt=[]
    for tb in range(n**k):
        s=[tb//(n**bt)%n for bt in range(k)];rt+=[s]
    return rt
def show(*inp,end='\n'):
    if show_flg:print(*inp,end=end)

YN=['YES','NO'];Yn=['Yes','No']
mo=10**9+7
inf=float('inf')
l_alp=string.ascii_lowercase
#sys.setrecursionlimit(10**7)
input=lambda: sys.stdin.readline().rstrip()

class Tree:
    def __init__(self,inp_size=None,init=True):
        self.LCA_init_stat=False
        if init:
            self.stdin(inp_size)
        return

    def stdin(self,inp_size=None,index=1):
        if inp_size==None:
            self.size=int(input())
        else:
            self.size=inp_size
        self.edges,_=GI(self.size,self.size-1,index=index)
        return
    
    def listin(self,ls,index=0):
        self.size=len(ls)+1
        self.edges,_=GI(self.size,self.size-1,ls,index=index)
        return

    def __str__(self):
        return  str(self.edges)

    def dfs(self,x,func=lambda prv,nx,dist:prv+dist,root_v=0):
        q=deque()
        q.append(x)
        v=[-1]*self.size
        v[x]=root_v
        while q:
            c=q.pop()
            for nb,d in self.edges[c]:
                if v[nb]==-1:
                    q.append(nb)
                    v[nb]=func(v[c],nb,d)
        return v

    def EulerTour(self,x,func=lambda prv,nx,dist:prv+1,root_v=0):
        q=deque()
        q.append((-1,x))
        depth=[None]*self.size
        depth[x]=root_v
        et=[]
        while q:
            cb,ce=q.pop()
            et.append(ce)
            for nb,d in self.edges[ce]:
                if depth[nb]==None:
                    q.append((nb,ce))
                    q.append((ce,nb))
                    depth[nb]=func(depth[ce],nb,d)
        vid=[[-1,-1]for i in range(self.size)]
        for i,j in enumerate(et):
            if vid[j][0]==-1:
                vid[j][0]=i
            else:
                vid[j][1]=i
        self.ETtable=et[:]
        self.ETdepth=[depth[i] for i in et]
        self.ETid=vid[:]
        return depth,et,vid
    
    def LCA_init(self,root):
        self.EulerTour(root,func=lambda prv,nx,dist:prv+dist,root_v=0)
        self.st=SparseTable(self.ETdepth,init_func=min,init_idl=inf)
        self.LCA_init_stat=True
        return
    
    def LCA(self,root,x,y):
        if self.LCA_init_stat==False:
            self.LCA_init(root)
        xin,xout=self.ETid[x]
        yin,yout=self.ETid[y]
        a=min(xin,yin)
        b=max(xout,yout,xin,yin)
        id_of_min_dep_in_et=self.st.query_id(a,b+1)
        #show((xin,xout),(yin,yout),(a,b),id_of_min_dep_in_et)
        return self.ETtable[id_of_min_dep_in_et]

class SparseTable: # O(N log N) for init, O(1) for query(l,r)
    def __init__(self,ls,init_func=min,init_idl=float('inf')):
        self.func=init_func
        self.idl=init_idl
        self.size=len(ls)
        self.N0=self.size.bit_length()
        self.table=[ls[:]]
        self.index=[list(range(self.size))]
        self.lg=[0]*(self.size+1)
        
        for i in range(2,self.size+1):
            self.lg[i]=self.lg[i>>1]+1

        for i in range(self.N0):
            tmp=[self.func(self.table[i][j],self.table[i][min(j+(1<<i),self.size-1)]) for j in range(self.size)]
            tmp_id=[self.index[i][j] if self.table[i][j]==self.func(self.table[i][j],self.table[i][min(j+(1<<i),self.size-1)]) else self.index[i][min(j+(1<<i),self.size-1)] for j in range(self.size)]
            self.table+=[tmp]
            self.index+=[tmp_id]
    
    # return func of [l,r)
    def query(self,l,r):
        #N=(r-l).bit_length()-1
        N=self.lg[r-l]
        return self.func(self.table[N][l],self.table[N][r-(1<<N)])
    
    # return index of which val[i] = func of v among [l,r)
    def query_id(self,l,r):
        #N=(r-l).bit_length()-1
        N=self.lg[r-l]
        a,b=self.index[N][l],self.index[N][r-(1<<N)]
        if self.table[0][a]==self.func(self.table[N][l],self.table[N][r-(1<<N)]):
            b=a
        return b
    
    def __str__(self):
        return str(self.table[0])
        
    def print(self):
        for i in self.table:
            print(*i)

show_flg=False
show_flg=True
ans=0


n,q=LI()
ls=[]
col=dict()
e_len=dict()
for i in range(n-1):
    a,b,c,d=LI_()
    d+=1
    ls+=[(a,b,d)]
    if a>b:
        a,b=b,a
    col[a*n+b]=c
    e_len[a*n+b]=d

tr=Tree(init=False)
tr.listin(ls,index=0)

root=0
dist=tr.dfs(root,func=lambda prv_v,nx,dist:prv_v+dist)
dep,et,vid=tr.EulerTour(root)



ad=[[0] for i in range(n)]
an=[[0] for i in range(n)]
index=[[] for i in range(n)]
for i in range(2*n-1-1):
    a,b=et[i],et[i+1]
    sign=1 if dep[a]<dep[b] else -1
    if a>b:
        a,b=b,a
    c=col[a*n+b]
    dd=e_len[a*n+b]*sign
    an[c]+=[an[c][-1]+sign]
    ad[c]+=[ad[c][-1]+dd]
    index[c]+=[i]
    

for i in range(q):
    x,y,u,v=LI_()
    y+=1
    ls+=[(a,b,d)]
    lca=tr.LCA(root,u,v)
    dist_u=dist[u]-dist[lca]
    dist_v=dist[v]-dist[lca]
    path=dist_u+dist_v
    
    ui=bisect.bisect_left(index[x],vid[u][0])
    vi=bisect.bisect_left(index[x],vid[v][0])
    #show(vi,bisect.bisect(index[x],vid[v][0]),(index[x],vid[v][0]))
    ai=bisect.bisect_left(index[x],vid[lca][0])
    ui=min(ui,len(index[x]))
    vi=min(vi,len(index[x]))
    ai=min(ai,len(index[x]))
    
    
    c_dist_u=ad[x][ui]-ad[x][ai]
    c_dist_v=ad[x][vi]-ad[x][ai]
    c_path=c_dist_u+c_dist_v
    c_n_u=an[x][ui]-an[x][ai]
    c_n_v=an[x][vi]-an[x][ai]
    c_n=c_n_u+c_n_v
    #ri=bisect.bisect_right(index[x],r)
    ans=path-c_path+c_n*y
    #show(ans,'col',x,(lca,(u,v)),path,(vid[lca][0],(vid[u][0],vid[v][0])),(ai,(ui,vi)),c_path,(c_dist_u,c_dist_v),index[x],'# c_path',(c_n_u,c_n_v))
    
    print(ans)

Submission status: Time Limit Exceeded

Solution code:
import sys,bisect,string,math,time,functools,random
from heapq import heappush,heappop,heapify
from collections import deque,defaultdict,Counter
from itertools import permutations,combinations,groupby
def Golf():*a,=map(int,open(0))
def I():return int(input())
def S_():return input()
def IS():return input().split()
def LS():return [i for i in input().split()]
def LI():return [int(i) for i in input().split()]
def LI_():return [int(i)-1 for i in input().split()]
def NI(n):return [int(input()) for i in range(n)]
def NI_(n):return [int(input())-1 for i in range(n)]
def StoLI():return [ord(i)-97 for i in input()]
def ItoS(n):return chr(n+97)
def LtoS(ls):return ''.join([chr(i+97) for i in ls])
def GI(V,E,ls=None,Directed=False,index=1):
    org_inp=[];g=[[] for i in range(V)]
    FromStdin=True if ls==None else False
    for i in range(E):
        if FromStdin:
            inp=LI()
            org_inp.append(inp)
        else:
            inp=ls[i]
        if len(inp)==2:
            a,b=inp;c=1
        else:
            a,b,c=inp
        if index==1:a-=1;b-=1
        aa=(a,c);bb=(b,c);g[a].append(bb)
        if not Directed:g[b].append(aa)
    return g,org_inp
def GGI(h,w,search=None,replacement_of_found='.',mp_def={'#':1,'.':0},boundary=1):
#h,w,g,sg=GGI(h,w,search=['S','G'],replacement_of_found='.',mp_def={'#':1,'.':0}) # sample usage
    mp=[boundary]*(w+2);found={}
    for i in range(h):
        s=input()
        for char in search:
            if char in s:
                found[char]=((i+1)*(w+2)+s.index(char)+1)
                mp_def[char]=mp_def[replacement_of_found]
        mp+=[boundary]+[mp_def[j] for j in s]+[boundary]
    mp+=[boundary]*(w+2)
    return h+2,w+2,mp,found
def TI(n):return GI(n,n-1)
def bit_combination(k,n=2):
    rt=[]
    for tb in range(n**k):
        s=[tb//(n**bt)%n for bt in range(k)];rt+=[s]
    return rt
def show(*inp,end='\n'):
    if show_flg:print(*inp,end=end)

YN=['YES','NO'];Yn=['Yes','No']
mo=10**9+7
inf=float('inf')
l_alp=string.ascii_lowercase
#sys.setrecursionlimit(10**7)
input=lambda: sys.stdin.readline().rstrip()

class Comb:
    def __init__(self,n,mo=10**9+7):
        self.fac=[0]*(n+1)
        self.inv=[1]*(n+1)
        self.fac[0]=1
        self.fact(n)
        for i in range(1,n+1):
            self.fac[i]=i*self.fac[i-1]%mo
            self.inv[n]*=i
            self.inv[n]%=mo
        self.inv[n]=pow(self.inv[n],mo-2,mo)
        for i in range(1,n):
            self.inv[n-i]=self.inv[n-i+1]*(n-i+1)%mo
        return
    
    def fact(self,n):
        return self.fac[n]
        
    def invf(self,n):
        return self.inv[n]

    def comb(self,x,y):
        if y<0 or y>x:
            return 0
        return self.fac[x]*self.inv[x-y]*self.inv[y]%mo

class Tree:
    def __init__(self,inp_size=None,init=True):
        self.LCA_init_stat=False
        if init:
            self.stdin(inp_size)
        return

    def stdin(self,inp_size=None,index=1):
        if inp_size==None:
            self.size=int(input())
        else:
            self.size=inp_size
        self.edges,_=GI(self.size,self.size-1,index=index)
        return
    
    def listin(self,ls,index=0):
        self.size=len(ls)+1
        self.edges,_=GI(self.size,self.size-1,ls,index=index)
        return

    def __str__(self):
        return  str(self.edges)

    def dfs(self,x,func=lambda prv,nx,dist:prv+dist,root_v=0):
        q=deque()
        q.append(x)
        v=[-1]*self.size
        v[x]=root_v
        while q:
            c=q.pop()
            for nb,d in self.edges[c]:
                if v[nb]==-1:
                    q.append(nb)
                    v[nb]=func(v[c],nb,d)
        return v

    def EulerTour(self,x,func=lambda prv,nx,dist:prv+1,root_v=0):
        q=deque()
        q.append((-1,x))
        depth=[None]*self.size
        depth[x]=root_v
        et=[]
        while q:
            cb,ce=q.pop()
            et.append(ce)
            for nb,d in self.edges[ce]:
                if depth[nb]==None:
                    q.append((nb,ce))
                    q.append((ce,nb))
                    depth[nb]=func(depth[ce],nb,d)
        vid=[[-1,-1]for i in range(self.size)]
        for i,j in enumerate(et):
            if vid[j][0]==-1:
                vid[j][0]=i
            else:
                vid[j][1]=i
        self.ETtable=et[:]
        self.ETdepth=[depth[i] for i in et]
        self.ETid=vid[:]
        return depth,et,vid
    
    def LCA_init(self,root):
        self.EulerTour(root,func=lambda prv,nx,dist:prv+dist,root_v=0)
        self.st=SparseTable(self.ETdepth,init_func=min,init_idl=inf)
        self.LCA_init_stat=True
        return
    
    def LCA(self,root,x,y):
        if self.LCA_init_stat==False:
            self.LCA_init(root)
        xin,xout=self.ETid[x]
        yin,yout=self.ETid[y]
        a=min(xin,yin)
        b=max(xout,yout,xin,yin)
        id_of_min_dep_in_et=self.st.query_id(a,b+1)
        #show((xin,xout),(yin,yout),(a,b),id_of_min_dep_in_et)
        return self.ETtable[id_of_min_dep_in_et]

class SparseTable: # O(N log N) for init, O(1) for query(l,r)
    def __init__(self,ls,init_func=min,init_idl=float('inf')):
        self.func=init_func
        self.idl=init_idl
        self.size=len(ls)
        self.N0=self.size.bit_length()
        self.table=[ls[:]]
        self.index=[list(range(self.size))]
        self.lg=[0]*(self.size+1)
        
        for i in range(2,self.size+1):
            self.lg[i]=self.lg[i>>1]+1

        for i in range(self.N0):
            tmp=[self.func(self.table[i][j],self.table[i][min(j+(1<<i),self.size-1)]) for j in range(self.size)]
            tmp_id=[self.index[i][j] if self.table[i][j]==self.func(self.table[i][j],self.table[i][min(j+(1<<i),self.size-1)]) else self.index[i][min(j+(1<<i),self.size-1)] for j in range(self.size)]
            self.table+=[tmp]
            self.index+=[tmp_id]
    
    # return func of [l,r)
    def query(self,l,r):
        #N=(r-l).bit_length()-1
        N=self.lg[r-l]
        return self.func(self.table[N][l],self.table[N][r-(1<<N)])
    
    # return index of which val[i] = func of v among [l,r)
    def query_id(self,l,r):
        #N=(r-l).bit_length()-1
        N=self.lg[r-l]
        a,b=self.index[N][l],self.index[N][r-(1<<N)]
        if self.table[0][a]==self.func(self.table[N][l],self.table[N][r-(1<<N)]):
            b=a
        return b
    
    def __str__(self):
        return str(self.table[0])
        
    def print(self):
        for i in self.table:
            print(*i)

show_flg=False
show_flg=True
ans=0


n,q=LI()
ls=[]
col=dict()
e_len=dict()
for i in range(n-1):
    a,b,c,d=LI_()
    d+=1
    ls+=[(a,b,d)]
    if a>b:
        a,b=b,a
    col[a*n+b]=c
    e_len[a*n+b]=d

tr=Tree(init=False)
tr.listin(ls,index=0)

root=0
dist=tr.dfs(root,func=lambda prv_v,nx,dist:prv_v+dist)
dep,et,vid=tr.EulerTour(root)



ad=[[0] for i in range(n)]
an=[[0] for i in range(n)]
index=[[] for i in range(n)]
for i in range(2*n-1-1):
    a,b=et[i],et[i+1]
    sign=1 if dep[a]<dep[b] else -1
    if a>b:
        a,b=b,a
    c=col[a*n+b]
    dd=e_len[a*n+b]*sign
    an[c]+=[an[c][-1]+sign]
    ad[c]+=[ad[c][-1]+dd]
    index[c]+=[i]
    

for i in range(q):
    x,y,u,v=LI_()
    y+=1
    ls+=[(a,b,d)]
    lca=tr.LCA(root,u,v)
    dist_u=dist[u]-dist[lca]
    dist_v=dist[v]-dist[lca]
    path=dist_u+dist_v
    
    ui=bisect.bisect_left(index[x],vid[u][0])
    vi=bisect.bisect_left(index[x],vid[v][0])
    #show(vi,bisect.bisect(index[x],vid[v][0]),(index[x],vid[v][0]))
    ai=bisect.bisect_left(index[x],vid[lca][0])
    ui=max(0,min(ui,len(index[x])))
    vi=max(0,min(vi,len(index[x])))
    ai=max(0,min(ai,len(index[x])))
    
    
    c_dist_u=ad[x][ui]-ad[x][ai]
    c_dist_v=ad[x][vi]-ad[x][ai]
    c_path=c_dist_u+c_dist_v
    c_n_u=an[x][ui]-an[x][ai]
    c_n_v=an[x][vi]-an[x][ai]
    c_n=c_n_u+c_n_v
    #ri=bisect.bisect_right(index[x],r)
    ans=path-c_path+c_n*y
    #show(ans,'col',x,(lca,(u,v)),path,(vid[lca][0],(vid[u][0],vid[v][0])),(ai,(ui,vi)),c_path,(c_dist_u,c_dist_v),index[x],'# c_path',(c_n_u,c_n_v))
    
    print(ans)