模非素数下的排列组合，简直凶残
调着调着就过了= =
都不知道怎么过的= =
直接上链接http://hi.baidu.com/aekdycoin/blog/item/147620832b567eb40df4d258.html
CODE：
#include<cstdio>
#include<iostream>
#include<cstring>
#include<algorithm>
#include<cmath>
using namespace std;
typedef long long ll;
ll a[3][50],pri[50],M[50],t[50];
ll ex_gcd(ll a,ll b,ll &x,ll &y) {
if (b==0) {x=1,y=0 ;return a;}
ex_gcd(b,a%b,x,y);
x=x-a/b*y;
swap(x,y);
return 0;
}
ll p;
int l,sum[50];
int fen(int p){
for (int i=2;i<=sqrt(p);i++) {
if (p%i==0) {
pri[++l]=i;
while (p%i==0) {
sum[l]++;
p/=i;
}
}
}
if (p>1) {pri[++l]=p;sum[l]=1;}
return 0;
}
ll power(ll x,ll y,ll mod){
if (y==0) return 1;
ll ans=power(x,y>>1,mod);
ans=ans*ans%mod;
if (y&1) ans=ans*x%mod;
return ans;
}
ll f[100101],cnt;
ll calcfac(ll n,ll p,ll pi){
if (n<pi) return f[n];
// printf("%lld %lld",pi,pri[1]);
ll seg=n/p,rem=n%p;
ll ret=power(f[p-1],seg,p);
ret=ret*f[rem]%p;
cnt+=n/pi;
ret=ret*calcfac(n/pi,p,pi)%p;
return ret;
}
ll china(ll *a,ll *b) {
ll tem,ans=0;
for (int i=2;i<=l;i++) {
ll x,y;
ex_gcd(b[i-1],b[i],x,y);
b[i]=b[i]*b[i-1];
a[i]=((x*(a[i]-a[i-1])*b[i-1]+a[i-1])%b[i]+b[i])%b[i];
}
return a[l];
}
ll b[51];
ll c(int n,int m){
for (int i=1;i<=l;i++) {
ll p=1;
for (int j=1;j<=sum[i];j++) p*=pri[i];
f[0]=1;
for (int j=1;j<p;j++) {
f[j]=f[j-1];
if (j%pri[i]==0) continue;
f[j]=(f[j]*j)%p;
}
cnt=0;ll ans,tem;
a[1][i]=calcfac(n,p,pri[i]);
tem=cnt;cnt=0;
a[2][i]=calcfac(m,p,pri[i]);
printf("%lld ",pri[1]);
a[3][i]=calcfac(n-m,p,pri[i]);
cnt=tem-cnt;
a[2][i]=a[3][i]*a[2][i]%p;
ex_gcd(a[2][i],p,ans,tem);
ans=(ans%p+p)%p;
a[1][i]=a[1][i]*ans%p*power(pri[i],cnt,p)%p;
b[i]=p;
}
return (china(a[1],b));
}
ll te[8];
int main(){
ll n,m;
ll tmp=0;
scanf("%lld %lld %lld",&p,&n,&m);
for (int i=1;i<=m;i++) {
scanf("%lld",&te[i]);
tmp+=te[i];
}
if (tmp>n) {printf("Impossible");return 0;}
fen(p);
for (int i=1;i<=l;i++) printf("%lld %lld ",pri[i],sum[i]);
ll ans=1;
for (int i=1;i<=m;i++) {
ans=ans*c(n,te[i])%p;
n-=te[i];
// if (ans==0) {printf("%d ",0);return 0;}
printf(" ");
}
printf("%lld",ans);
return 0;
}