#include <bits/stdc++.h>
using namespace std;
using ll = long long;
namespace SegmentTree {
constexpr int N = 1 << 18;
array<ll, 2> t[N * 2];
array<ll, 2> operator+(const array<ll, 2> &a, const array<ll, 2> &b) {
return {a[0] + b[0], max(b[1], a[1] + b[0])};
}
void pull(int x) {
t[x] = t[x << 1] + t[x << 1 | 1];
}
void modify(int x, ll v) {
x += N;
t[x][0] = v, t[x][1] = max(0LL, v);
while (x >>= 1) {
pull(x);
}
}
array<ll, 2> rangeQuery(int l, int r) {
array<ll, 2> L{}, R{};
for (l += N, r += N; l < r; r >>= 1, l >>= 1) {
if (l & 1) {
L = L + t[l++];
}
if (r & 1) {
R = t[--r] + R;
}
}
return L + R;
}
}
template<typename T>
struct Fenwick {
int n;
vector<T> a;
Fenwick() = default;
explicit Fenwick(int n) : n(n), a(n + 1) {}
void modify(int x, T v) {
for (int i = x + 1; i <= n; i += i & -i) {
a[i] += v;
}
}
void modify(int l, int r, T v) {
if (l >= r) return;
modify(l, v), modify(r, -v);
}
T sum(int x) {
T ans = 0;
for (int i = x + 1; i > 0; i -= i & -i) {
ans += a[i];
}
return ans;
}
T rangeSum(int l, int r) { //[l, r)
if (l >= r) return 0;
return sum(r - 1) - sum(l - 1);
}
int kth(T k) {
int x = 0;
for (int i = 1 << __lg(n); i; i >>= 1) {
if (x + i <= n && k > a[x + i]) {
x += i;
k -= a[x];
}
}
return x;
}
};
int main() {
ios::sync_with_stdio(false);
cin.tie(nullptr);
int n, m, q;
cin >> n >> m >> q;
vector<vector<int>> qr(n + 1), ql(n), que(n);
vector<ll> L(q), R(q), ans(q), K(q);
for (int i = 0; i < q; ++i) {
int t;
cin >> t >> L[i] >> R[i];
L[i] -= 1;
if (t == 1 || t == 2) {
ql[L[i]].push_back(i);
qr[R[i]].push_back(i);
} else if (t == 3) {
que[L[i]].push_back(i);
}
if (t == 1) {
cin >> R[i] >> K[i];
} else if (t == 2) {
cin >> K[i];
K[i] = -K[i];
} else {
L[i] = -1;
}
}
Fenwick<ll> fn(q);
for (int i = 0; i < n; ++i) {
for (int j : qr[i]) {
SegmentTree::modify(j, 0);
if (K[j] > 0) {
fn.modify(j, -K[j]);
}
}
for (int j : ql[i]) {
SegmentTree::modify(j, K[j]);
if (K[j] > 0) {
fn.modify(j, K[j]);
}
}
for (int j : que[i]) {
ll have = SegmentTree::rangeQuery(0, j)[1];
if (have >= R[j]) {
ans[j] = R[fn.kth(fn.sum(j) - (have - R[j]))];
}
}
}
for (int i = 0; i < q; ++i) {
if (L[i] == -1) {
cout << ans[i] << '\n';
}
}
return 0;
}
