#include <bits/stdc++.h>
#define x first
#define y second
#define all(v) v.begin(), v.end()
#define chkmax(a, b) a = max(a, b)
#define chkmin(a, b) a = min(a, b)
//#define int ll
using namespace std;
typedef long long ll;
typedef vector<ll> vi;
typedef vector<vi> vvi;
typedef pair<ll, ll> pii;
typedef vector<pii> vii;
const int MAX_N = 3e5 + 5;
const ll infinity = 1e9;
struct PosFunction {
//g(t) = max(l, min(r, t))
ll l = 0, r = 0;
PosFunction() {}
PosFunction(ll l, ll r): l(l), r(r) {}
ll operator()(ll t) {
return max(l, min(r, t));
}
PosFunction operator()(PosFunction g) {
if (r < g.l) return {r, r};
else if (g.r < l) return {l, l};
return {max(l, g.l), min(r, g.r)};
}
};
struct TimeFunction {
//f(t) = max(a, b + t)
ll a = 0, b = 0;
TimeFunction() {}
TimeFunction(ll a, ll b): a(a), b(b) {}
ll operator()(ll t) {
return max(a, b + t);
}
TimeFunction operator()(TimeFunction f, PosFunction g) {
ll a2 = f(0) + (*this)(g(0));
ll b2 = f(infinity) + (*this)(g(infinity)) - infinity;
return {a2, b2};
}
};
struct Seg {
int n;
vector<TimeFunction> tim;
vector<PosFunction> pos;
Seg() {}
Seg(int m) {
for (n = 1; n < m; n <<= 1);
tim.resize(2 * n), pos.resize(2 * n);
}
void Pull(int i) {
tim[i] = tim[i << 1 | 1](tim[i << 1], pos[i << 1]);
pos[i] = pos[i << 1 | 1](pos[i << 1]);
}
void Update(int i, int l1, int r1, int ind, int a, int b) {
if (a + 1 == b) {
pos[ind] = PosFunction(l1, r1);
tim[ind] = TimeFunction(0, -r1);
return;
}
if (i < ((a + b) >> 1)) Update(i, l1, r1, ind << 1, a, (a + b) >> 1);
else Update(i, l1, r1, ind << 1 | 1, (a + b) >> 1, b);
Pull(ind);
}
ll Query(int l, int r, ll st, ll et) {
vi indl, indr;
for (l += n, r += n; l < r; l >>= 1, r >>= 1) {
if (l & 1) indl.push_back(l++);
if (r & 1) indr.push_back(--r);
}
while (!indl.empty()) indr.push_back(indl.back()), indl.pop_back();
PosFunction p = pos[indr.back()];
TimeFunction t = tim[indr.back()];
indr.pop_back();
while (!indr.empty()) {
int i = indr.back();
indr.pop_back();
t = tim[i](t, p);
p = pos[i](p);
}
ll ans = t(st), po = p(st);
return ans + max<ll>(0, po - et);
}
};
int L[MAX_N], R[MAX_N], t[MAX_N], a[MAX_N], b[MAX_N], c[MAX_N], d[MAX_N];
ll ans[MAX_N];
int32_t main() {
ios_base::sync_with_stdio(false);
cin.tie(0);
int n, q;
cin >> n >> q;
for (int i = 0; i + 1 < n; i++) cin >> L[i] >> R[i];
for (int i = 0; i < q; i++) {
cin >> t[i] >> a[i] >> b[i] >> c[i];
if (t[i] == 2) cin >> d[i];
}
for (int i = 0; i < q; i++) a[i]--, c[i]--;
for (int i = 0; i + 1 < n; i++) R[i]--;
for (int ti = 0; ti < 2; ti++) {
Seg seg(n);
for (int i = 0; i + 1 < n; i++) {
seg.Update(i, L[i] - i, R[i] - i, 1, 0, seg.n);
}
for (int i = 0; i < q; i++) {
if (t[i] == 1) {
seg.Update(a[i], b[i] - a[i], c[i] - a[i], 1, 0, seg.n);
} else {
if (a[i] <= c[i]) ans[i] = seg.Query(a[i], c[i], b[i] - a[i], d[i] - c[i]);
}
}
reverse(L, L + n - 1), reverse(R, R + n - 1);
for (int i = 0; i < q; i++) {
if (t[i] == 1) a[i] = n - 2 - a[i];
else a[i] = n - 1 - a[i], c[i] = n - 1 - c[i];
}
}
for (int i = 0; i < q; i++) {
if (t[i] == 2) cout << ans[i] << '\n';
}
}
