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- #include <bits/stdc++.h>
- using namespace std;
- using lli = long long;
- const lli Mod = 1e9 + 7;
- lli Pow(lli a, lli n){
- lli ans = 1;
- a = a % Mod;
- for(;n > 0;n = n / 2, a = (a * a) % Mod){
- if(n & 1) ans = (ans * a) % Mod;
- }
- return ans;
- }
- lli Query(lli n, lli a){
- return ( (((Pow(2 * a, 2 * n - 1) - Pow(2 * a, n - 1)) % Mod + Mod) % Mod) * Pow(2 * a - 1, Mod - 2) ) % Mod;
- }
- int main(){
- lli Q;
- scanf("%lld", &Q);
- while(Q --){
- lli n, a;
- scanf("%lld%lld", &n, &a);
- printf("%lld\n", Query(n, a));
- }
- return 0;
- }
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