#include <bits/stdc++.h>
#include <bits/extc++.h>
using namespace __gnu_pbds;
using namespace std;
// #pragma GCC optimize("Ofast")
// #pragma GCC optimize ("unroll-loops")
// #pragma GCC target("sse,sse2,sse3,ssse3,sse4,popcnt,abm,mmx,avx,tune=native")
#define ff first
#define sc second
#define pb push_back
#define ll long long
#define pll pair<ll, ll>
#define pii pair<int, int>
#define ull unsigned long long
#define all(x) (x).begin(),(x).end()
#define rall(x) (x).rbegin(),(x).rend()
mt19937 rng(chrono::steady_clock::now().time_since_epoch().count());
mt19937_64 rngl(chrono::steady_clock::now().time_since_epoch().count());
// #define int long long
// #define int unsigned long long
// #define ordered_set(T) tree<T, null_type, less<T>, rb_tree_tag, tree_order_statistics_node_update>
// #define ordered_multiset(T) tree<T, null_type, less_equal<T>, rb_tree_tag, tree_order_statistics_node_update>
void open_file(string filename) {
freopen((filename + ".in").c_str(), "r", stdin);
freopen((filename + ".out").c_str(), "w", stdout);
}
// const ll mod = 1e9 + 7;
// const ll mod = 998244353;
const ll inf = 1e9;
const ll biginf = 1e18;
const int maxN = 1e5 + 25;
vector<int> qs[maxN];
int par[maxN], sz[maxN];
void make_set() {
for (int i = 1; i < maxN; i++) {
par[i] = i; sz[i] = 1;
}
}
int find_set(int x) {
if (par[x] == x)
return x;
return par[x] = find_set(par[x]);
}
void union_set(int x, int y) {
x = find_set(x);
y = find_set(y);
if (x == y) return;
if (sz[x] < sz[y]) swap(x, y);
sz[x] += sz[y]; par[y] = x;
}
void solve() {
int n, m, q;
cin >> n >> m >> q;
int x[q + 1], y[q + 1], l[q + 1], r[q + 1], ans[q + 1];
for (int i = 1; i <= q; i++) {
cin >> x[i] >> y[i];
l[i] = 1; r[i] = m; ans[i] = -1;
} while (1) {
bool f = 1; make_set();
for (int i = 1; i <= q; i++) {
if (l[i] > r[i]) continue;
qs[(l[i] + r[i]) / 2].pb(i); f = 0;
} if (f) break;
for (int i = 1; i <= m; i++) {
for (int j = m - i + 1; j <= n; j += m - i + 1) union_set(m - i + 1, j);
for (int j : qs[i]) {
if (find_set(x[j]) == find_set(y[j])) {
ans[j] = i; r[j] = i - 1;
} else l[j] = i + 1;
}
} for (int i = 1; i < maxN; i++) qs[i].clear();
} for (int i = 1; i <= q; i++) cout << ans[i] << '\n';
}
int32_t main() {
ios_base::sync_with_stdio(false);
cin.tie(nullptr); cout.tie(nullptr);
int t = 1;
// cin >> t;
while (t--) {
solve();
cout << '\n';
}
return 0;
}
