欧拉定理相关

a ^ a ^ a ^ … ^ b % m

#include 
#define fo(i,a,b) for(i=a;i<=b;i++)
using namespace std;
const int maxn=1e6+5;
typedef long long ll;
int minDiv[maxn],phi[maxn],sum[maxn];
int T,flag,i;
long long a,x,ep,t,m,res;
void genPhi()
{
     
	for (int i=1;i<maxn;i++)
	{
     
		minDiv[i]=i;
	}
	for (int i=2;i*i<maxn;i++)
	{
     
		if (minDiv[i]==i)
		{
     
			for (int j=i*i;j<maxn;j+=i)
			{
     
				minDiv[j]=i;
			}
		}
	}
	phi[1]=1;
	for (int i=2;i<maxn;i++)
	{
     
		phi[i]=phi[i/minDiv[i]];
		if ((i/minDiv[i]) % minDiv[i]==0)
		{
     
			phi[i]*=minDiv[i];
		}
		else
		{
     
			phi[i]*=minDiv[i]-1;
		} 
	}
}
long long q_p(long long a,long long x,long long MOD)
{
     
	long long e = a; long long res = 1;
	while (x)
	{
     
		if (x&1) res = (res * e) % MOD;
		e = (e * e) % MOD;
		x >>= 1;
	}
	return res;
}
long long dfs(long long x,long long t,long long m)
{
     
	if (m == 1) return 0;
	if (t == 1) return q_p(a,x,m);
	ep = dfs(x,t-1,phi[m]);
	ep = ep % phi[m] + phi[m];
	return q_p(a,ep,m);
}
int main()
{
     
	genPhi();
	scanf("%d",&T);
	while (T--)
	{
     
		scanf("%lld%lld%lld",&a,&t,&m);
		//if (m == 1) {cout<<0<
		x = 1; flag = 0; res = 1;
		while (t--)
		{
     
			res = 1;
			if (flag == 0) fo(i,1,x) {
     res = res * a; if (res > phi[m]) {
     flag = 1; break;}}
			if (flag == 0) {
     x = res; continue;}
			t++; break;
		}
		if (t > 0) res = dfs(x,t,m);
		cout<<res%m<<endl;
	}
	return 0;
}