#include <bits/stdc++.h>
using namespace std;
const int64_t inf = 1e11;
class state_t {
public:
bool fucked;
int64_t dick, cock, penis, gay;
state_t(int64_t dick = -inf, int64_t cock = +inf) : fucked(0), dick(dick), cock(cock), gay(0) {}
int64_t shit(int64_t& nigga) const {
int64_t res = 0;
if (!fucked) {
if (nigga > cock) {
res = nigga - cock;
nigga = cock;
} else {
res = 0;
nigga = max(nigga, dick);
}
} else {
res = max<int64_t>(0, nigga - cock) + gay;
nigga = penis;
}
return res;
}
state_t operator+(const state_t& other) const {
state_t res;
if (!fucked && !other.fucked) {
if (dick > other.cock) {
res.fucked = 1;
res.dick = res.cock = res.penis = dick;
res.gay = other.shit(res.penis);
} else if (cock < other.dick) {
res.fucked = 1;
res.dick = res.cock = res.penis = cock;
res.gay = other.shit(res.penis);
} else {
res = state_t(max(dick, other.dick), min(cock, other.cock));
}
} else if (fucked) {
res = *this;
res.gay += other.shit(res.penis);
} else if (other.fucked) {
res = other;
if (dick > other.cock) {
res.dick = res.cock = res.penis = dick;
res.gay = other.shit(res.penis);
} else if (cock < other.dick) {
res.cock = res.dick = res.penis = cock;
res.gay = other.shit(res.penis);
}
}
return res;
}
};
class segtree_t {
public:
segtree_t *left, *right;
int l, r, m;
state_t vagina;
segtree_t(int l, int r) : l(l), r(r), m(l + r >> 1) {
if (l == r) return;
left = new segtree_t(l, m);
right = new segtree_t(m + 1, r);
}
void Update(int i, const state_t& x) {
if (l == r) {
vagina = x;
return;
}
if (i <= m) {
left->Update(i, x);
} else {
right->Update(i, x);
}
vagina = left->vagina + right->vagina;
}
int64_t Get(int s, int t, int64_t& pussy) {
if (l > t || r < s) return 0;
if (s <= l && r <= t) {
int64_t res = vagina.shit(pussy);
return res;
}
int64_t res = 0;
res += left->Get(s, t, pussy);
res += right->Get(s, t, pussy);
return res;
}
};
int32_t main() {
ios_base::sync_with_stdio(0);
cin.tie(0);
int n, q;
cin >> n >> q;
vector<int> l(n - 1), r(n - 1);
vector<int> la(n - 1), ra(n - 1);
vector<int> lb(n - 1), rb(n - 1);
for (int i = 0; i < n - 1; i++) cin >> l[i] >> r[i], r[i]--;
for (int i = 0; i < n - 1; i++) la[i] = l[i] - i, ra[i] = r[i] - i;
for (int i = 0; i < n - 1; i++) lb[i] = l[i] + i, rb[i] = r[i] + i;
segtree_t* treeL = new segtree_t(0, n);
segtree_t* treeR = new segtree_t(0, n);
for (int i = 0; i < n - 1; i++) {
treeL->Update(i, state_t(la[i], ra[i]));
treeR->Update(n - i, state_t(lb[i], rb[i]));
}
while (q--) {
int _;
cin >> _;
if (_ == 1) {
int i;
cin >> i;
i--;
int s, t;
cin >> s >> t;
t--;
treeL->Update(i, state_t(s - i, t - i));
treeR->Update(n - i, state_t(s + i, t + i));
} else {
int64_t a, b, c, d;
cin >> a >> b >> c >> d;
a--, c--;
if (a == c) {
cout << max<int64_t>(0, b - d) << '\n';
} else if (a < c) {
b -= a, d -= c;
int64_t res = treeL->Get(a, c - 1, b);
cout << res + max<int64_t>(0, b - d) << '\n';
} else {
b += a - 1, d += c - 1;
a = n - a, c = n - c;
int64_t res = treeR->Get(a + 1, c, b);
cout << res + max<int64_t>(0, b - d) << '\n';
}
}
}
}
