【POJ2773】Happy 2006 欧几里德

#include<cstdio>
#include<cstring>
#include<cstring>
#include<iostream>
#include<algorithm>
#include<cmath>
using namespace std;
#define Maxn 1000010
#define LL long long

int p[Maxn],len;

int gcd(int a,int b)
{
if(b==0) return a;
return gcd(b,a%b);
}

int main()
{
int m,k;
while(scanf("%d%d",&m,&k)!=EOF)
{
if(m==1) {printf("%d\n",k);continue;}
len=0;
for(int i=1;i<=m;i++) if(gcd(i,m)==1) p[++len]=i;
int ans;
if(k%len==0) ans=(k/len-1)*m+p[len];
else ans=k/len*m+p[k%len];
printf("%d\n",ans);
}
return 0;
}