#include <cstdio>
#include <algorithm>
#include <utility>
using namespace std;
typedef pair<int,int> ii;
int n;
ii input[300005];
inline int read() {
int x = 0;
char ch = getchar_unlocked();
while (ch >= '0' && ch <= '9'){
x = (x << 3) + (x << 1) + ch - '0';
ch = getchar_unlocked();
}
return x;
}
struct stats{
int l_time,r_time;
long long time_used;
long long powers_used;
stats(int a,int b,int c, int d){
l_time=a;
r_time=b;
time_used=c;
powers_used=d;
}
stats(stats *i, stats *j){
unions(i,j);
}
stats(stats *i){
l_time=i->l_time;
r_time=i->r_time;
time_used=i->time_used;
powers_used=i->powers_used;
}
void unions(stats *l,stats *r){
powers_used=l->powers_used+r->powers_used;
time_used=l->time_used+r->time_used;
int left=l->l_time+l->time_used,right=l->r_time+l->time_used;
if (max(left,r->l_time)<=min(right,r->r_time)){
l_time=max(left,r->l_time)-l->time_used;
r_time=min(right,r->r_time)-l->time_used;
}
else if (right<r->l_time){
time_used+=r->l_time-right;
l_time=l->r_time;
r_time=l_time;
}
else{
powers_used+=left-r->r_time;
time_used-=left-r->r_time;
l_time=l->l_time;
r_time=l_time;
}
}
};
struct node{
int s,e,m;
stats *val;
node *l,*r;
node (int _s,int _e){
s=_s,e=_e,m=(s+e)>>1;
if (s==e){
val=new stats(input[s].first,input[s].second-1,1,0);
}
else{
l=new node(s,m);
r=new node(m+1,e);
val=new stats(l->val,r->val);
}
}
stats* query(int i,int j){
if (s==i && e==j) return val;
else if (j<=m) return l->query(i,j);
else if (m<i) return r->query(i,j);
else return new stats(l->query(i,m),r->query(m+1,j));
}
void update(int i){
if (s==e){
val=new stats(input[s].first,input[s].second-1,1,0);
}
else{
if (i<=m) l->update(i);
else r->update(i);
val->unions(l->val,r->val);
}
}
}*root;
struct rnode{
int s,e,m;
stats *val;
rnode *l,*r;
rnode (int _s,int _e){
s=_s,e=_e,m=(s+e)>>1;
if (s==e){
val=new stats(input[n-s].first,input[n-s].second-1,1,0);
}
else{
l=new rnode(s,m);
r=new rnode(m+1,e);
val=new stats(l->val,r->val);
}
}
stats* query(int i,int j){
if (s==i && e==j) return val;
else if (j<=m) return l->query(i,j);
else if (m<i) return r->query(i,j);
else return new stats(l->query(i,m),r->query(m+1,j));
}
void update(int i){
if (s==e){
val=new stats(input[n-s].first,input[n-s].second-1,1,0);
}
else{
if (i<=m) l->update(i);
else r->update(i);
val->unions(l->val,r->val);
}
}
}*rroot;
int main(){
//freopen("input.txt","r",stdin);
int q;
n=read();
q=read();
if (n==1){
int a,b;
while (q--){
read(),read();
a=read();
read();
b=read();
if (a>b) printf("%d\n",a-b);
else printf("0\n");
}
return 0;
}
for (int x=1;x<n;x++) input[x].first=read(),input[x].second=read();
root=new node(1,n-1);
rroot=new rnode(1,n-1);
int a,b,c,d;
int type;
stats *res;
int fin_time;
while (q--){
type=read();
if (type==2){
a=read();
b=read();
c=read();
d=read();
if (a<c) res=new stats(root->query(a,c-1));
else if (c<a) res=new stats(rroot->query(n-a+1,n-c));
else{
if (b>d) printf("%d\n",b-d);
else printf("0\n");
continue;
}
//printf("%lld %lld %lld %lld\n",res->l_time,res->r_time,res->time_used,res->powers_used);
fin_time=max(b,res->l_time);
if (b>res->r_time){
res->powers_used+=b-res->r_time;
fin_time=res->r_time;
}
fin_time+=res->time_used;
if (d<fin_time){
res->powers_used+=fin_time-d;
}
printf("%lld\n",res->powers_used);
}
else{
a=read();
b=read();
c=read();
input[a]=ii(b,c);
root->update(a);
rroot->update(n-a);
}
}
}
