#include <bits/stdc++.h>
#define fi first
#define se second
#define FOR(i, a, b) for(int i=(a); i<=(b); ++i)
#define REP(i, a, b) for(int i=(a); i>=(b); --i)
#define BIT(x, i) (((x) >> (i)) & 1)
#define MASK(i) (1LL << (i))
#define sz(v) (int)(v).size()
#define ALL(v) (v).begin(),(v).end()
using namespace std;
typedef long long ll;
typedef pair<int,int> pii;
typedef pair<ll,ll> pll;
template <class T1, class T2> bool ckmax(T1 &a, T2 b){ if (a < b) {a = b; return 1;}return 0;}
template <class T1, class T2> bool ckmin(T1 &a, T2 b){ if (a > b) {a = b; return 1;}return 0;}
const int N = 1e6 + 5;
const int mod = 1e9 + 7;
const int base = 311;
const ll INF = 1e18;
// Author: rexdino
int n, m, q;
pii Q[N];
int l[N], r[N], ans[N];
vector<int> adj[N];
struct DSU{
vector<int> par;
DSU(int _n){
par.assign(n + 2, -1);
}
int Find(int u){
return par[u] < 0 ? u : par[u] = Find(par[u]);
}
void join(int u, int v){
u = Find(u); v = Find(v);
if (u == v) return;
if (par[u] > par[v]) swap(u, v);
par[u] += par[v];
par[v] = u;
}
};
void solve(){
cin >> n >> m >> q;
FOR(i, 1, q) cin >> Q[i].fi >> Q[i].se;
FOR(i, 1, q){
l[i] = 1, r[i] = m;
}
FOR(i, 1, 20){
FOR(i, 1, q){
if (l[i] > r[i]) continue;
int mid = (l[i] + r[i]) >> 1;
adj[mid].push_back(i);
}
DSU dsu = DSU(n);
REP(i, m, 1){
for (int j=2*i;j<=n;j+=i){
dsu.join(j, j - i);
}
for (int id : adj[i]){
if (dsu.Find(Q[id].fi) == dsu.Find(Q[id].se)){
ans[id] = i;
l[id] = i + 1;
} else r[id] = i - 1;
// cerr << id << " " << i << " " << ans[id] << "\n";
}
adj[i].clear();
}
}
FOR(i, 1, q) cout << m - ans[i] + 1 << "\n";
}
signed main(){
#define NAME "main"
if (fopen(NAME".inp", "r")){
freopen(NAME".inp", "r", stdin);
freopen(NAME".out", "w", stdout);
}
ios_base::sync_with_stdio(0); cin.tie(0);
int t = 1;
// cin >> t;
while(t--) solve();
// cerr << "Time elapsed: " << (1.0 * clock() / CLOCKS_PER_SEC) << "s\n";
return 0;
}
