Problem - D - Codeforces

牛客和codeforce都有

递归处理l,r，终点是l==r && mod=1

用扩展欧拉定理

// Problem: D. Power Tower
// Contest: Codeforces - Codeforces Round 454 (Div. 1, based on Technocup 2018 Elimination Round 4)
// URL: https://codeforces.com/problemset/problem/906/D
// Memory Limit: 256 MB
// Time Limit: 4500 ms
// 
// Powered by CP Editor (https://cpeditor.org)

#include<iostream>
#include<map>
using namespace std;
typedef long long ll;
const int N=1e5+9;
ll a[N];
map<int,int> mp;
ll phi(ll x){
	if(mp[x]){//记忆存储
		return mp[x];
	}
	ll t=x;
	ll res=x;
	for(int i=2;i<=x/i;i++){
		if(x%i==0){
			res=res/i*(i-1);
			while(x%i==0){
				x/=i;
			}
		}
	}
	if(x>1){
		res=res/x*(x-1);
	}
	mp[t]=res;
	return res;
}
ll mo(ll x,ll mod){
	return x<mod?x:(x%mod+mod);
}
ll qmi(ll a,ll b,ll mod){//扩展欧拉定理
	ll res=1;
	while(b){
		if(b&1){
			res=mo(res*a,mod);
		}
		b>>=1;
		a=mo(a*a,mod);
	}
	return res;
}
ll work(int l,int r,ll mod){
	if(l==r || mod==1){
		return mo(a[l],mod);
	}else{
		return qmi(a[l],work(l+1,r,phi(mod)),mod);
	}
}
int main(){
	ll n,m;
	cin>>n>>m;
	for(int i=1;i<=n;i++){
		cin>>a[i];
	}
	int q;
	cin>>q;
	for(int i=1;i<=q;i++){
		int l,r;
		cin>>l>>r;
		cout<<work(l,r,m)%m<<'\n';
	}
	return 0;
}