杂七杂八的一堆东西

Posted 2020-10-13 baka

 1 #include<bits/stdc++.h>
 2 #define N 100010
 3 using namespace std;
 4 typedef long long ll;
 5 ll a[N];
 6 int p;
 7 ll pow(ll y,int z,int p){
 8     y%=p;ll ans=1;
 9     for(int i=z;i;i>>=1,y=y*y%p)if(i&1)ans=ans*y%p;
10     return ans;
11 }
12 ll C(ll n,ll m){
13     if(m>n)return 0;
14     return ((a[n]*pow(a[m],p-2,p))%p*pow(a[n-m],p-2,p)%p);
15 }
16 ll Lucas(ll n,ll m){
17     if(!m)return 1;
18     return C(n%p,m%p)*Lucas(n/p,m/p)%p;
19 }
20 inline int read(){
21     int f=1,x=0;char ch;
22     do{ch=getchar();if(ch==‘-‘)f=-1;}while(ch<‘0‘||ch>‘9‘);
23     do{x=x*10+ch-‘0‘;ch=getchar();}while(ch>=‘0‘&&ch<=‘9‘);
24     return f*x;
25 }
26 int main(){
27     int T=read();
28     while(T--){
29         int n=read(),m=read();p=read();
30         a[0]=1;
31         for(int i=1;i<=p;i++)a[i]=(a[i-1]*i)%p;
32         cout<<Lucas(n+m,n)<<endl;
33     }
34 }

Lucas