FJ省队集训DAY4 T2

 1 #include<cstdio>
 2 #include<iostream>
 3 #include<cmath>
 4 #include<cstring>
 5 #include<algorithm>
 6 #include<vector>
 7 using namespace std;
 8 typedef unsigned long long ll;
 9 ll a,mod=1,L=1;
10 ll tr[4],b[4],tmp[4];
11 std::vector <ll> ans,ans2;
12 ll read(){
13     ll t=0,f=1;char ch=getchar();
14     while (ch<‘0‘||ch>‘9‘){if (ch==‘-‘)f=-1;ch=getchar();}
15     while (‘0‘<=ch&&ch<=‘9‘){t=t*10+ch-‘0‘;ch=getchar();}
16     return t*f;
17 }
18 ll Mul(ll a,ll b){
19     if (mod<=1000000000)
20      return a*b%mod;
21     else 
22      return b?((Mul(a,b>>16)<<16)+a*(b&65535))%mod:0; 
23 }
24 void Mul(ll *a,ll *b) {
25     static ll c[4];
26     c[0]=(Mul(a[0],b[0])+Mul(a[1],b[2]))%mod;
27     c[1]=(Mul(a[0],b[1])+Mul(a[1],b[3]))%mod;
28     c[2]=(Mul(a[2],b[0])+Mul(a[3],b[2]))%mod;
29     c[3]=(Mul(a[2],b[1])+Mul(a[3],b[3]))%mod;
30     memcpy(a,c,sizeof c);
31 }
32 void init(ll *tr,ll L){
33     static ll tc[4];
34     tc[0]=0; tc[1]=1; tc[2]=1; tc[3]=1;
35     tr[0]=1; tr[1]=0; tr[2]=0; tr[3]=1;
36     for (;L;L>>=1,Mul(tc,tc))
37         if (L&1) Mul(tr,tc);
38 }
39 int main(){
40     cin>>a;ans.push_back(0);mod=1;L=1;
41     for (int p=1;p<=13;p++){
42         mod*=10;
43         init(tr,L);
44         init(b,0);
45         ll L2=0;
46         do{
47          for (int i=0;i<ans.size();i++){
48                 init(tmp,ans[i]+L2);
49                 if (tmp[2]==a%mod) ans2.push_back(ans[i]+L2);
50          }
51          L2+=L;
52          Mul(b,tr);
53         }while(b[0]!=1||b[1]!=0||b[2]!=0||b[3]!=1);
54         std::swap(ans,ans2);
55         ans2.clear();
56         L=L2;
57     }
58     if (ans.empty()) puts("-1");
59     std::cout<<ans[0]<<std::endl;
60 }