我怎么又开始刷水题了啊/该死
由二项式定理
计算系数
$a^k,b^k$的计算用快速幂实现
这里组合数用记搜实现
#include<bits/stdc++.h>
#define int long long
using namespace std;
const int N = 1010;
const int mod = 10007;
int C[N][N];
int dfs(int n,int m){
if(C[n][m]!=-1)return C[n][m];
if(n == m||m == 0){
C[n][m] = 1;
}
else{
C[n][m] =(dfs(n-1,m)+dfs(n-1,m-1))%mod;
}
return C[n][m];
}
int muli(int a,int b){
int res = 1;
while(b){
if(b&1)res = (res * a)%mod;
a = (a*a)%mod;
b >>= 1;
}
return res;
}
signed main(){
memset(C,-1,sizeof C);
int a,b,c,d,e;cin>>a>>b>>c>>d>>e;
int ans = (muli(a,d) * muli(b,e))%mod;
ans = (ans*dfs(c,min(d,e)))%mod;
cout<<ans;
return 0;
}