A Boring Question (打表)

时间:2022-02-15 10:32:17

  题意:由m个0到n组合的数的相邻两项的组合数的乘积。

  思路:好好打表!!!找规律!!!

#include<bits/stdc++.h>
using namespace std; typedef long long ll; const int maxn = 1e3 + ;
const int maxm = 1e6 + ;
const int mod = 1e9 + ; ll mypow(ll a, ll p, ll mo){
ll ret = ;
while(p){
if(p & ) ret = ret * a % mod;
a = a * a % mo;
p >>= ;
}
return ret;
} int main(){
ll n, m;
int T;scanf("%d", &T);
for(int ncase = ; ncase <= T; ncase ++){
scanf("%lld%lld", &n, &m);
ll ans = (mypow(m, n + , mod) - + mod ) % mod;
ans = ans * mypow(m - , mod - , mod) % mod;
printf("%lld\n", ans);
}
return ;
}