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11
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#include<bits/stdc++.h>
#define N 3250
using namespace std;typedef struct
{int v;long long flow;
}ss;
ss edg[N*N];
vector<int>edges[N];
int now_edges=0;
int fl[N][N];void init()
{for(int i=0;i<N;i++)edges[i].clear();now_edges=0;
}void addedge(int u,int v,long long flow)
{fl[u][v]+=flow;edges[u].push_back(now_edges);edg[now_edges++]=(ss){v,flow};edges[v].push_back(now_edges);edg[now_edges++]=(ss){u,0};
}int dis[N],S,T;bool bfs()
{queue<int>q;q.push(S);memset(dis,0,sizeof(dis));dis[S]=1;while(!q.empty()){int now=q.front();q.pop();int Size=edges[now].size();for(int i=0;i<Size;i++){ss e=edg[edges[now][i]];if(e.flow>0&&dis[e.v]==0){dis[e.v]=dis[now]+1;q.push(e.v);}}}if(dis[T]==0)return 0;return 1;
}int current[N];long long dfs(int now,long long maxflow)
{if(now==T)return maxflow;int Size=edges[now].size();for(int i=current[now];i<Size;i++){current[now]=i;ss &e=edg[edges[now][i]];if(e.flow>0&&dis[e.v]==dis[now]+1){long long Flow=dfs(e.v,min(maxflow,e.flow));if(Flow!=0){fl[now][e.v]-=Flow;fl[e.v][now]+=Flow;e.flow-=Flow;edg[edges[now][i]^1].flow+=Flow;return Flow;}}}return 0;
}long long dinic()
{long long ans=0,flow;while(bfs()){memset(current,0,sizeof(current));while(flow=dfs(S,LLONG_MAX/2))ans+=flow;}return ans;
}int f(int n)  //返回球数是n的时候的最小路径覆盖数
{init();S=2*n+1;T=2*n+2;for(int i=1;i<=n;i++){for(int j=i+1;j<=n;j++)if((int)sqrt(i+j)*(int)sqrt(i+j)==(i+j))addedge(2*i-1,2*j,1);    addedge(S,2*i-1,1);addedge(2*i,T,1);}return n-dinic();
}int vis[N]={0};void ff(int x,int ans) //dfs寻找每条路径上的点，由于题目的特殊性可以从小到大按顺序寻找
{printf("%d ",x);vis[x]=1;for(int i=x+1;i<=ans;i++)if(fl[i*2][x*2-1]){ff(i,ans);break;}
}int main()
{int n;scanf("%d",&n);int Left=1,Right=1600,ans=1;while(Left<=Right){int mid=(Left+Right)/2;if(f(mid)<=n){ans=mid;Left=mid+1;}else Right=mid-1;}printf("%d\n",ans);for(int i=1;i<=ans;i++){if(!vis[i])ff(i,ans),printf("\n");;}return 0;
}