#include<bits/stdc++.h> using namespace std; const int maxn=105; bool edge[maxn][maxn]; int vertn; // int dfs_ans,found,mcp[maxn],suf[maxn][maxn]; // dfs void dfs(int d){ // begin with d =1 which means choose one point if(suf[d][0]==0){ if(dfs_ans<d) { dfs_ans=d; found=1; } return ; } for(int i=1;i<=suf[d][0]&&!found;++i) { if(d+suf[d][0]-i+1<=dfs_ans) break;// cut if(d+mcp[suf[d][i]]<=dfs_ans) break;// cut for(int j=i+1;j<=suf[d][0];++j){ if(edge[suf[d][i]][suf[d][j]]) suf[d+1][++suf[d+1][0]]=suf[d][j]; } dfs(d+1); suf[d+1][0]=0; } } int max_cluster(){ mcp[vertn+1]=0; for(int i=vertn;i>=1;i--) { for(int j=i+1;j<=vertn;++j) if(edge[i][j]) suf[1][++suf[1][0]]=j; dfs(1); found=0; suf[1][0]=0; mcp[i]=dfs_ans; } return mcp[1]; } bool check(int x){ int s=sqrt(x)+0.5; return s*s==x; } int main(){ vertn=100; for(int i=1;i<=vertn;++i){ for(int j=1;j<=vertn;++j){ if(check(i)||check(j)||check(i+j)) edge[i][j]=0; else edge[i][j]=1; } } cout<<max_cluster()<<endl; }