题解: 先放代码: #include <bits/stdc++.h> #define ll long long using namespace std; const ll mod=1e9+7; ll T,n,m; ll quickPower(ll a, ll b) { ll ans = 1,base=a; while(b) { if(b & 1) ans = ans*base%mod; base = base*base%mod; b >>= 1; } return ans%mod; } int main() ...