#pragma GCC optimize("O3")
#pragma GCC optimize("unroll-loops")
#include <bits/stdc++.h>
using namespace std;
#define trav(a, x) for(auto& a : x)
#define FOR(i, a, b) for (int i=(a); i<=(signed)(b); i++)
#define ROF(i, a, b) for (int i=(a); i>=(signed)(b); i--)
#define F0R(i, a) for (int i=0; i<(signed)(a); i++)
#define vi vector<int>
#define f first
#define s second
#define all(v) (v).begin(), (v).end()
typedef long long ll;
const ll mod = 998244353, inf = mod*mod;
template <class S, S (*op)(S, S), S (*e)()> struct segtree {
public:
int ceil_pow2(int n) {
int x = 0;
while ((1U << x) < (unsigned int)(n)) x++;
return x;
}
segtree() : segtree(0) {}
segtree(int n) : segtree(std::vector<S>(n, e())) {}
segtree(const std::vector<S>& v) : _n(int(v.size())) {
log = ceil_pow2(_n);
size = 1 << log;
d = std::vector<S>(2 * size, e());
for (int i = 0; i < _n; i++) d[size + i] = v[i];
for (int i = size - 1; i >= 1; i--) {
update(i);
}
}
void set(int p, S x) {
assert(0 <= p && p < _n);
p += size;
d[p] = x;
for (int i = 1; i <= log; i++) update(p >> i);
}
S get(int p) {
assert(0 <= p && p < _n);
return d[p + size];
}
S prod(int l, int r) {
assert(0 <= l && l <= r && r <= _n);
S sml = e(), smr = e();
l += size;
r += size;
while (l < r) {
if (l & 1) sml = op(sml, d[l++]);
if (r & 1) smr = op(d[--r], smr);
l >>= 1;
r >>= 1;
}
return op(sml, smr);
}
S all_prod() { return d[1]; }
template <bool (*f)(S)> int max_right(int l) {
return max_right(l, [](S x) { return f(x); });
}
template <class F> int max_right(int l, F f) {
assert(0 <= l && l <= _n);
assert(f(e()));
if (l == _n) return _n;
l += size;
S sm = e();
do {
while (l % 2 == 0) l >>= 1;
if (!f(op(sm, d[l]))) {
while (l < size) {
l = (2 * l);
if (f(op(sm, d[l]))) {
sm = op(sm, d[l]);
l++;
}
}
return l - size;
}
sm = op(sm, d[l]);
l++;
} while ((l & -l) != l);
return _n;
}
template <bool (*f)(S)> int min_left(int r) {
return min_left(r, [](S x) { return f(x); });
}
template <class F> int min_left(int r, F f) {
assert(0 <= r && r <= _n);
assert(f(e()));
if (r == 0) return 0;
r += size;
S sm = e();
do {
r--;
while (r > 1 && (r % 2)) r >>= 1;
if (!f(op(d[r], sm))) {
while (r < size) {
r = (2 * r + 1);
if (f(op(d[r], sm))) {
sm = op(d[r], sm);
r--;
}
}
return r + 1 - size;
}
sm = op(d[r], sm);
} while ((r & -r) != r);
return 0;
}
private:
int _n, size, log;
std::vector<S> d;
void update(int k) { d[k] = op(d[2 * k], d[2 * k + 1]); }
};
using S = int;
S op (S a, S b) {
return min(a, b);
}
S e() {
return mod;
}
int main()
{
ios_base::sync_with_stdio(0); cin.tie(0);
int n, m, q; cin >> n >> m >> q;
vector<vector<int>> adj(2*n);
vector<int> par(2*n);
int id = n;
auto find = [&] (auto find, int u) -> int {
return par[u] == u ? u : par[u] = find(find, par[u]);
};
F0R(i, n) {
par[i] = i;
}
vector<int> id_e(2*n-1);
ROF(i, m, 1) {
auto unite = [&] (int u, int v) -> void {
u = find(find, u), v = find(find, v);
if (u == v) return;
par[u] = par[v] = par[id] = id;
adj[id] = {u, v};
id_e[id] = m-i+1;
id++;
};
vector<int> mults;
for(int j = i; j <= n; j += i) {
mults.push_back(j-1);
}
F0R(i, mults.size()-1) {
unite(mults[i], mults[i+1]);
}
}
// F0R(_, 2*n-1) {
// cout << _ << ": ";
// trav(x, adj[_]) cout << x << " ";
// cout << "\n";
// }
// FOR(i, n, 2*n-2) cout << id_e[i] << " ";
// cout << "\n";
vector<int> tin(2*n-1), et1, i_tin(8*n);
auto dfs1 = [&] (auto dfs1, int u) -> void {
tin[u] = et1.size();
i_tin[et1.size()] = u;
et1.push_back(tin[u]);
trav(v, adj[u]) {
dfs1(dfs1, v);
et1.push_back(tin[u]);
}
};
dfs1(dfs1, 2*n-2);
segtree<S, op, e>ST(et1);
auto lca = [&] (int u, int v) -> int {
int uu = tin[u];
int vv = tin[v];
if(uu > vv) swap(uu, vv);
int g = ST.prod(uu, vv+1);
return i_tin[g];
};
F0R(_, q) {
int u, v; cin >> u >> v;
u--;
v--;
int x = lca(u, v);
int ads = id_e[x];
cout << ads << "\n";
}
return 0;
}
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