C

http://codeforces.com/contest/842/problem/C

树 dp

一个数的质因数有限，用set存储，去重

#include <cstdio>
#include <cstdlib>
#include <cmath>
#include <cstring>
#include <time.h>
#include <string>
#include <set>
#include <map>
#include <list>
#include <stack>
#include <queue>
#include <vector>
#include <bitset>
#include <ext/rope>
#include <algorithm>
#include <iostream>
using namespace std;
#define ll long long
#define minv 1e-6
#define inf 1e9
#define pi 3.1415926536
#define E  2.7182818284
const ll mod=1e9+7;//998244353
const int maxn=2e5+10;

struct node
{
    int d;
    node* next;
}*e[maxn];

set<int>y[maxn]; //delete one
int a[maxn],x[maxn],value[maxn];
bool vis[maxn]={0};

void dfs(int d)
{
    set<int>::iterator i;
    int dd;

    value[d]=x[d];
    for (i=y[d].begin();i!=y[d].end();i++)
        value[d]=max(value[d],*i);

    node* p=e[d];
    vis[d]=1;
    while (p)
    {
        dd=p->d;
        if (!vis[dd])
        {
            x[dd]=__gcd(x[d],a[dd]);
            y[dd].insert(x[d]);
            for (i=y[d].begin();i!=y[d].end();i++)
                y[dd].insert(__gcd(a[dd],*i));
            if (d==1)
                y[dd].insert(a[dd]);
            dfs(dd);
        }
        p=p->next;
    }
    //free memory
    y[d].clear();
}

int main()
{
    node* p;
    int n,X,y,i;
    scanf("%d",&n);
    for (i=1;i<=n;i++)
        scanf("%d",&a[i]);
    for (i=1;i<n;i++)
    {
        scanf("%d%d",&X,&y);
        p=(node*) malloc (sizeof(node));
        p->d=y;
        p->next=e[X];
        e[X]=p;

        p=(node*) malloc (sizeof(node));
        p->d=X;
        p->next=e[y];
        e[y]=p;
    }

    x[1]=a[1];
    dfs(1);

    for (i=1;i<n;i++)
        printf("%d ",value[i]);
    printf("%d",value[i]);
    return 0;
}
/*
3
6 10 12
1 2
2 3
*/