題目鏈接:https://www.luogu.org/problem/P1592
AC代碼:
#include<bits/stdc++.h>
using namespace std;
typedef long long ll;
const int maxn=1e6+10;
ll a[maxn];
int main()
{
ll n,k;
cin>>n>>k;
ll cnt=0;
for(ll i=1;i<n;i++){
if(__gcd(n,i)==1){
a[++cnt]=i;
}
}
// for(int i=1;i<=cnt;i++){
// cout<<a[i]<<" ";
// }
// cout<<endl;
ll s=k/cnt;//歐拉函數的週期性
ll s1=k%cnt;
ll ans=n*s+a[s1];
cout<<ans<<endl;
return 0;
}