USACO Section 2.2 循环数 Runaround Numbers

OJ:http://www.luogu.org/problem/show?pid=1467

#include<iostream>
#include<vector>
#include<cstring>
using namespace std;
int v[10],pv[64];
bool judge(long long x){
	vector<int> a,b;
	memset(v,0,sizeof(v));
	while(x>=10){
		a.push_back(x%10);
		if(v[x%10])
			return false;
		v[x%10]=1;
		x/=10;
	}
	if(v[x])
		return false;
	if(v[0])
		return false;
	b.push_back(x);
	for(int i=a.size()-1;i>=0;i--) b.push_back(a[i]);
	int p=0;
	memset(pv,0,sizeof(pv));
	for(int i=1;i<b.size();i++){
		if(pv[p]) return false;
		pv[p]=1;
		p+=b[p];
		p%=b.size();
	}
	return (p+b[p])%b.size()==0;
}
int main()
{
	long long n;
	cin>>n;
	while(!judge(++n));
	cout<<n;
	return 0;
}