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fft

#include<bits/stdc++.h>
using namespace std;
typedef long long LL;
typedef long long ll;
const double pi=acos(-1);
typedef complex<double> cp;
int n,a,q;
const int mod=100003;
const int size=1e5+5;
vector<int> co[size<<2];
cp x[size],y[size];
int b[size],s[size];
int quick_pow(int a,int b){int ans=1;while(b){if(b&1) ans=1LL*a*ans%mod;a=1LL*a*a%mod;b>>=1;} return ans;}
int fac[size];
int invfac[size];
void init()
{
	fac[0]=1;
	for(int i=1;i<=n;i++) fac[i]=1LL*fac[i-1]*i%mod;
	invfac[n]=quick_pow(fac[n],mod-2);
	for(int i=n-1;i>=0;i--) invfac[i]=1LL*invfac[i+1]*(i+1)%mod;
}
namespace Polynomial_multiplication{
	int n, m, rev[size << 2];
	cp a[size << 2], b[size << 2];
	void init(int len) {
		for (n = 1, m = 0; n <= len; n <<= 1, m++);
		for (int i = 0; i < n; ++i) {
			rev[i] = rev[i >> 1] >> 1 | (i & 1) << (m - 1);
			a[i] = cp(0, 0);
			b[i] = cp(0, 0);
		}
	}
	void builda(vector<int> x,int len){for(int i=0;i<=len;i++) a[i]=cp(x[i],0);}
	void builda(int x[],int len){for(int i=0;i<=len;i++) a[i]=cp(x[i],0);}
	void buildb(vector<int> x,int len){for(int i=0;i<=len;i++) b[i]=cp(x[i],0);}
	void buildb(int x[],int len){for(int i=0;i<=len;i++) b[i]=cp(x[i],0);}
	void fft(cp *a, int f) {
		for (int i = 0; i < n; ++i)if (i < rev[i])swap(a[i], a[rev[i]]);
		for (int i = 1; i < n; i <<= 1) {
			double alpha = pi / i;
			if (f == -1)alpha = -pi / i;
			for (int k = 0; k < i; ++k) {
				cp w = cp(cos(alpha*k), sin(alpha*k));
				for (int j = k; j < n; j += (i << 1)) {
					cp x = w * a[j + i];
					a[j + i] = a[j] - x;
					a[j] += x;
				}
			}
		}
		if(f==-1) for(int i=0;i<n;i++) a[i]/=n;
	}
	void calc(vector<int> &v,int len) {
		fft(a, 1); fft(b, 1);
		for (int i = 0; i < n; ++i)a[i] *= b[i];
		fft(a, -1);
		for(int i=0;i<=len;i++) v.push_back(LL(a[i].real()+0.5)%mod);
	}
} 
void solve(int id,int l,int r)
{
	if(l==r)
	{
		co[id].push_back(1);
		co[id].push_back(b[l]);
		return ;
	}
	int mid=(l+r)/2;
	solve(id<<1,l,mid);
	solve(id<<1|1,mid+1,r);
	Polynomial_multiplication::init(r-l+1);
	Polynomial_multiplication::builda(co[id<<1],mid-l+1);
	Polynomial_multiplication::buildb(co[id<<1|1],r-mid);
	Polynomial_multiplication::calc(co[id],r-l+1);
}

int ans[size];
inline LL combi(int k,int n){return k>n?0:1LL*fac[n]*invfac[k]%mod*invfac[n-k]%mod;}
int main()
{
	scanf("%d%d%d",&n,&a,&q);
	init();
	for(int i=1;i<=n;i++) scanf("%d",&s[i]);
	for(int i=1;i<=n;i++) b[i]=quick_pow(a,s[i]%(mod-1));
	solve(1,1,n);
	int inva_1=quick_pow(a-1,mod-2);
	for(int i=1;i<=n;i++) ans[i]=(co[1][i]-combi(i,n)+mod)%mod*inva_1%mod;
	for(int i=1;i<=q;i++)
	{
		int k;
		scanf("%d",&k);
		printf("%d
",ans[k]);
	}
	return 0;
}

leetcode对于树dp来说可以直接用地址当作key值

void dfs1(TreeNode* root) {//可以直接使用map<uint32_t,int>
        sum[root] = root -> val;
        if (root -> left) {
            dfs1(root -> left, sum);
            sum[root] += sum[root->left];
        }
        if (root->right) {
            dfs1(root->right, sum);
            sum[root] += sum[root->right];
        }
    }
  
    int dfs2(TreeNode* root) {
        double l, r;
        if (root->left)
           l=dfs2(root->left);
        if (root->right)
           r=[root]+=dfs2(root->right);
           dp[root]+=l+r;
        return dp[root];
    }