#include<iostream>#include<cstdio>#include<cstring>#include<cmath>using namespace std;const double EP=1e-10;int main(){ int n,i,j,touch[1010],sum,tmax; bool flag[1010]; double r[1010], x[1010],lmax; while(scanf("%d", &n)!=EOF){ lmax=0;sum=0;tmax=n-1; memset(touch,-1,sizeof(touch)); memset(flag,0,sizeof(flag)); for(i=0; i<n; i++){ scanf("%lf", &r[i]); x[i]=r[i]; } for(i=1; i<n; i++){ for(j=0; j<i; j++){ if(x[j]+2*sqrt(r[i]*r[j])-x[i]>EP){ x[i]=x[j]+2*sqrt(r[i]*r[j]); touch[i]=j; } } if(x[i]+r[i]-lmax>EP){ lmax=x[i]+r[i]; tmax=i; } } for(i=0; i<n; i++) for(j=touch[i]+1; j<i; j++) if(!flag[j]){ flag[j]=1; sum++; } for(i=tmax+1;i<n;i++) if(!flag[i]){ flag[i]=1; sum++; } printf("%dn", sum); for(i=0; i<n; i++) if(flag[i]) printf("%dn",i+1); } return 0; }
