A. Division
题意 给定p和q,找一个最大的x,x能整除p,但是q不能整除x
分析
x肯定是p的唯一分解定理的一部分,所以可以考虑从x中删除一下,使得q整除x。由于p太大,分解它肯定会超时,所以可以分解q,然后看q的每一个质因数的次方,p的这个质因数次方是否都小于它。如果都小于它,那么答案就是p,否则就让某个质数的次方,让p这边小于q(这里暴力一下就行)
代码
#include <bits/stdc++.h>
#define ios ios_base::sync_with_stdio(0),cin.tie(0),cout.tie(0)
#define debug_in freopen("in.txt","r",stdin)
#define debug_out freopen("out.txt","w",stdout);
#define pb push_back
#define all(x) x.begin(),x.end()
#define fs first
#define sc second
using namespace std;
typedef long long ll;
typedef unsigned long long ull;
typedef pair<ll,ll> pii;
const ll maxn = 1e6+10;
const ll maxM = 1e6+10;
const ll inf = 1e8;
const ll inf2 = 1e17;
template<class T>void read(T &x){
T s=0,w=1;
char ch=getchar();
while(ch<'0'||ch>'9'){if(ch=='-')w=-1;ch=getchar();}
while(ch>='0'&&ch<='9') s=s*10+ch-'0',ch=getchar();
x = s*w;
}
template<class H, class... T> void read(H& h, T&... t) {
read(h);
read(t...);
}
void pt(){ cout<<'\n';}
template<class H, class ... T> void pt(H h,T... t){ cout<<" "<<h; pt(t...);}
//--------------------------------------------
int T;
ll a,b;
int P[maxn],tail;
bool vis[maxn];
map<int,int> mp;
ll A,B;
void initP(int N){
vis[1] = 1;
for(int i = 2;i<=N;i++){
if(!vis[i]) P[tail++] = i;
for(int j = 0;j<tail && P[j] <= N/i;j++){
vis[P[j] * i] = 1;
if(i % P[j] == 0) break;
}
}
}
ll ksm(ll a,ll b){
ll res = 1;
while(b){
if(b&1) res = res * a;
b>>=1;
a*=a;
}
return res;
}
void solve(){
read(A,B);
ll a = A,b = B;
mp.clear();
for(int i = 0;i<tail && P[i] * P[i]<=b;i++){
if(b % P[i] == 0){
int cnt = 0;
while(b % P[i] == 0){
cnt ++;
b/=P[i];
}
mp[P[i]] = cnt;
}
}
if(b > 1) mp[b] = 1;
int find = 0;
for(auto pp:mp){
ll p = pp.fs,cnt = pp.sc;
ll coun = 0,a = A;
while(a%p == 0){
coun++;
a/=p;
}
if(coun < cnt){
find = 1;
break;
}
}
if(find){
printf("%lld\n",A);
}else{
ll ans = 0;
for(auto pp:mp){
ll p = pp.fs,cnt = pp.sc;
ll coun = 0,a = A;
while(a%p == 0){
coun++;
a/=p;
}
if(coun >= cnt){
ans = max(ans,A/ksm(p,coun - cnt + 1));
}
}
printf("%lld\n",ans);
}
}
int main(){
// debug_in;
initP(1000000);
read(T);
while(T--){
solve();
}
return 0;
} 
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