#include <iostream>
#include <string>
#include <vector>
#include <queue>
#include <deque>
#include <stack>
#include <set>
#include <map>
#include <unordered_map>
#include <unordered_set>
#include <cstring>
#include <cmath>
#include <cstdlib>
#include <algorithm>
#include <random>
#include <iomanip>
#include <functional>
#include <cassert>
using namespace std;
typedef long long ll;
int main() {
ios_base::sync_with_stdio(false); cin.tie(0);
#ifdef LOCAL
freopen("input.txt", "r", stdin);
#endif
int n, q;
cin >> n >> q;
vector <int> l(n - 1), r(n - 1);
for (int i = 0; i < n - 1; ++i) {
cin >> l[i] >> r[i];
--r[i];
}
for (int tt = 0; tt < q; ++tt) {
int t;
cin >> t;
if (t == 1) {
int p, s, e;
cin >> p >> s >> e;
--p;
l[p] = s;
r[p] = e - 1;
} else {
int a, b, c, d;
cin >> a >> b >> c >> d;
--a, --c;
ll ans = 0;
int tm = b;
if (a <= c) {
for (int i = a; i < c; ++i) {
ans += max(0, tm - r[i]);
tm = min(tm, r[i]);
tm = max(tm, l[i]);
++tm;
}
ans += max(0, tm - d);
} else {
for (int i = a - 1; i >= c; --i) {
ans += max(0, tm - r[i]);
tm = min(tm, r[i]);
tm = max(tm, l[i]);
++tm;
}
ans += max(0, tm - d);
}
cout << ans << '\n';
}
}
}
