【小米oj】纯位数 - dogenya

时间复杂度本人没有证明，但是暴力交上去过了

 1 #define mm(a) memset(a,0,sizeof(a));
 2 #define max(x,y) (x)>(y)?(x):(y)
 3 #define min(x,y) (x)<(y)?(x):(y)
 4 #define Fopen freopen("1.in","r",stdin); freopen("m.out","w",stdout);
 5 #define rep(i,a,b) for(int i=(a);i<=(b);i++)
 6 #define per(i,b,a) for(int i=(b);i>=(a);i--)
 7 #include<bits/stdc++.h>
 8 typedef long long ll;
 9 #define PII pair<ll,ll>
10 using namespace std;
11 const int INF=0x3f3f3f3f;
12 const int MAXN=(int)2e5 + 5;
13 const ll mod=10000019;
14 int n;
15 bool ck(int x)
16 {
17     int now=n;
18     int temp=now%x;
19     now/=x;
20     while(now){
21         if(now%x!=temp)return 0;
22         now/=x;
23     }
24     return 1;
25 }
26 int main()
27 {
28     scanf("%d",&n);
29     for(int i=2;i<=n+1;i++){
30         if(ck(i))return printf("%d\n",i),0;
31     }
32     return 0;
33 }