1 #include<bits/stdc++.h>
2 using namespace std;
3 const int N=60,M=4010,oo=2e9;
4 int n,ss=4000,tt=4001,f[M];
5 bool vis[M];
6 struct Edge{
7 int from,to,flow,cap;
8 Edge(int _from=0,int _to=0,int _flow=0,int _cap=0):from(_from),to(_to),flow(_flow),cap(_cap){}
9 };
10 int edge_tot;
11 Edge edge[100500];
12 vector<int>point[M];
13 void add_edge(int f,int t,int c){
14 edge[edge_tot]=Edge(f,t,0,c);
15 point[f].push_back(edge_tot++);
16 edge[edge_tot]=Edge(t,f,0,0);
17 point[t].push_back(edge_tot++);
18 return;
19 }
20 int level[M];
21 bool bfs(){
22 memset(level,0,sizeof(level));
23 queue<int>q;
24 q.push(ss);
25 level[ss]=1;
26 int x;
27 while(!q.empty()){
28 x=q.front();q.pop();
29 for(int i=0;i<point[x].size();i++){
30 Edge e=edge[point[x][i]];
31 if(e.cap>e.flow&&!level[e.to]){
32 int nxt=edge[point[x][i]].to;
33 level[nxt]=level[x]+1;
34 q.push(nxt);
35 }
36 }
37 }
38 return level[tt];
39 }
40 int dfs(int k,int a){
41 if(k==tt||!a) return a;
42 int temp,ans=0;
43 for(int i=0;i<point[k].size();i++){
44 Edge& e=edge[point[k][i]];
45 if(e.cap>e.flow&&level[e.to]==level[k]+1&&(temp=dfs(e.to,min(a,e.cap-e.flow)))){
46 ans+=temp,a-=temp;
47 e.flow+=temp,edge[point[k][i]^1].flow-=temp;
48 }
49 if(!a) return ans;
50 }
51 return ans;
52 }
53 int dinic(){
54 int ans=0;
55 while(bfs())
56 ans+=dfs(ss,oo);
57 return ans;
58 }
59 int main(){
60 scanf("%d",&n);
61 int ans,t1,t2;
62 for(ans=1;1;ans++){
63 add_edge(ss,(ans<<1)-1,1);add_edge((ans<<1),tt,1);
64 for(int i=1;i<ans;i++){
65 t1=i+ans,t2=sqrt(t1);
66 if(t2*t2==t1) add_edge((ans<<1)-1,(i<<1),1);
67 }
68 t1=dinic();
69 if(ans-t1>n) break;
70 for(int i=0;i<edge_tot;i++) edge[i].flow=0;
71 }
72 ans--;
73 printf("%d\n",ans);
74 for(int i=1;i<=ans;i++)
75 for(int j=0;j<point[(i<<1)-1].size();j++)
76 if(edge[point[(i<<1)-1][j]].flow>0){f[(edge[point[(i<<1)-1][j]].to)>>1]=i;break;}
77 for(int i=1;i<=ans;i++){
78 if(vis[i]) continue;
79 printf("%d ",i);
80 vis[i]=1,t1=f[i];
81 while(t1){
82 printf("%d ",t1);
83 vis[t1]=1,t1=f[t1];
84 }
85 printf("\n");
86 }
87 return 0;
88 }
