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注意边界问题  sqrt(mod)要上取整  n^0=1 要和未出现的数特判区分开

#include<bits/stdc++.h>
using namespace std;
#define ll long long
ll n,mod,ans;
inline ll ksm(ll a,ll p)
 {ll re=1;
  while(p)
   {if(p&1) re=re*a%mod;
    p>>=1; a=a*a%mod;
   }
  return re;
 }
 map<ll,ll> s;
int main()
 {
  int t; scanf("%d",&t);
  while(t--)
  {scanf("%lld%lld%lld",&mod,&n,&ans);  // n^k =ans mod(mod)
                                                                     // ans*n^(-x*cmp)= n^(y) mod(mod)  k=x*cmp+y;         x--[0,cmp]  y--[0,cmp)
   ll cmp=ceil(sqrt(mod)),tmp=1; bool biao=1;
   for(ll i=0;i<cmp;i++)
    {if(!s[tmp]) s[tmp]=i;  //printf("%lld,%lld\n",i,tmp);
      tmp=tmp*n%mod;
    }
    ll hehe=ksm(n,mod-2);
   for(ll i=0;i<=cmp;i++)
    {tmp=ksm(hehe,i*cmp)*ans%mod;      // printf("%lld,%lld\n",i,tmp);
     if(s[tmp]!=0 || tmp==1) {biao=0; printf("%lld\n",i*cmp+s[tmp]); break;}
    }
    if(biao) printf("-l\n");
   tmp=1;
   for(ll i=0;i<cmp;i++) s[tmp]=0,tmp=tmp*n%mod;
  }

 return 0;
 }