#include <bits/stdc++.h>
using namespace std;
int main() {
ios::sync_with_stdio(false);
cin.tie(0);
int n, q;
cin >> n >> q;
vector<int> l, r;
if (n > 1) {
l.resize(n - 1);
r.resize(n - 1);
}
for (int i = 0; i < n - 1; ++i) {
cin >> l[i] >> r[i];
--r[i];
}
while (q--) {
int t;
cin >> t;
if (t == 1) {
int p, s, e;
cin >> p >> s >> e;
--p, --e;
l[p] = s;
r[p] = e;
}
if (t == 2) {
int a, b, c, d;
cin >> a >> b >> c >> d;
--a, --c;
bool f = a > c;
if (a > c) {
reverse(begin(l), end(l));
reverse(begin(r), end(r));
a = n - a - 1;
c = n - c - 1;
}
long long ans = 0;
for (int i = a; i < c; ++i) {
if (b > r[i]) {
ans += b - r[i];
b = r[i];
}
if (b < l[i]) {
b = l[i];
}
++b;
}
if (b > d) {
ans += b - d;
b = d;
}
cout << ans << "\n";
if (f) {
reverse(begin(l), end(l));
reverse(begin(r), end(r));
}
}
}
return 0;
}
