#include<cmath>
#include<stack>
#include<queue>
#include<cstdio>
#include<cctype>
#include<vector>
#include<cstdlib>
#include<cstring>
#include<iostream>
#include<algorithm>
using namespace std;
typedef long long ll;
const int INF=1e9;
const int N=5e4+5;
inline int read(){int X=0,w=0;char ch=0;while(!isdigit(ch)){w|=ch=='-';ch=getchar();}while(isdigit(ch))X=(X<<3)+(X<<1)+(ch^48),ch=getchar();return w?-X:X;
}
struct point{int x,y,b1,b2,id;
}p[N];
int n,b[N],c[N],d[N],e[N],l1,l2,l3,l4;
int to[3][N],lft[N],straight[N],rigt[N];
int f[N],g[N],flor[N],num[N];
vector<int>ty[N];
inline bool cmpx(point a,point b){return a.x<b.x;
}
inline bool cmpy(point a,point b){return a.y>b.y;
}
void LSH(){sort(b+1,b+l1+1);sort(c+1,c+l2+1);sort(d+1,d+l3+1);sort(e+1,e+l4+1);l1=unique(b+1,b+l1+1)-b-1,l2=unique(c+1,c+l2+1)-c-1;l3=unique(d+1,d+l3+1)-d-1,l4=unique(e+1,e+l4+1)-e-1;for(int i=1;i<=n;i++){p[i].x=lower_bound(b+1,b+l1+1,p[i].x)-b;p[i].y=lower_bound(c+1,c+l2+1,p[i].y)-c;p[i].b1=lower_bound(d+1,d+l3+1,p[i].b1)-d;p[i].b2=lower_bound(e+1,e+l4+1,p[i].b2)-e;}
}
void init(){LSH();sort(p+1,p+n+1,cmpy);for(int i=1;i<=n;i++){int id=p[i].id;to[0][id]=lft[p[i].b2];to[1][id]=straight[p[i].x];to[2][id]=rigt[p[i].b1];lft[p[i].b2]=id;straight[p[i].x]=id;rigt[p[i].b1]=id;}sort(p+1,p+n+1,cmpx);for(int i=1;i<=n;i++){ty[p[i].y].push_back(p[i].id);flor[p[i].id]=p[i].y;num[p[i].id]=ty[p[i].y].size()-1;}
}
int pre[N],lrs[N];
void output(int id){if(id!=lrs[id]){int fll=flor[id];if(num[id]<num[lrs[id]]){for(int i=num[id]-1;i>=0;i--)printf("%d ",ty[fll][i]);for(int i=num[id]+1;i<=num[lrs[id]];i++)printf("%d ",ty[fll][i]);}else{int sz=ty[fll].size();for(int i=num[id]+1;i<sz;i++)printf("%d ",ty[fll][i]);for(int i=num[id]-1;i>=num[lrs[id]];i--)printf("%d ",ty[fll][i]);}}id=lrs[id];if(pre[id]){printf("%d ",pre[id]);output(pre[id]);}
}
void work1(){init();for(int i=l2;i>=1;i--){int maxn=0,id=0,sz=ty[i].size();for(int j=0;j<sz;j++){//处理直行和向右再左走int I=ty[i][j];int J1=to[0][I],J2=to[1][I],J3=to[2][I];if(J1&&g[I]<f[J1])g[I]=f[J1],pre[I]=J1;if(J2&&g[I]<f[J2])g[I]=f[J2],pre[I]=J2;if(J3&&g[I]<f[J3])g[I]=f[J3],pre[I]=J3;if(maxn>g[I]+1)f[I]=maxn,lrs[I]=id;else f[I]=g[I]+1,lrs[I]=I;if(sz-j+g[I]>maxn)maxn=sz-j+g[I],id=I;}maxn=id=0;for(int j=sz-1;j>=0;j--){//处理向左再右走int I=ty[i][j];if(maxn>f[I])f[I]=maxn,lrs[I]=id;if(g[I]+j+1>maxn)maxn=g[I]+j+1,id=I;}}printf("%d\n",f[n]-1);output(n);puts("");
}
struct node{int to,nxt,w;
}edge[N*10];
int cnt,head[N],S,T,du[N];
int cur[N],lev[N],dui[N];
bool ok[N];
inline void adde(int u,int v,int w){edge[++cnt].to=v;edge[cnt].w=w;edge[cnt].nxt=head[u];head[u]=cnt;edge[++cnt].to=u;edge[cnt].w=0;edge[cnt].nxt=head[v];head[v]=cnt;
}
inline void add(int u,int v){for(int i=head[u];i!=-1;i=edge[i].nxt)if(edge[i].to==v)return;du[u]--;du[v]++;adde(u,v,INF-1);
}
bool bfs(int m){int r;for(int i=1;i<=m;i++){cur[i]=head[i];lev[i]=-1;}dui[r=0]=S;lev[S]=0;for(int i=0;i<=r;i++){int u=dui[i];for(int j=head[u];j!=-1;j=edge[j].nxt){int v=edge[j].to,w=edge[j].w;if(lev[v]==-1&&w){lev[v]=lev[u]+1;dui[++r]=v;if(v==T)return 1;}}}return 0;
}
int dinic(int u,int flow,int m){if(u==m)return flow;int res=0,delta;for(int &i=cur[u];i!=-1;i=edge[i].nxt){int v=edge[i].to;if(lev[v]>lev[u]&&edge[i].w){delta=dinic(v,min(flow,edge[i].w),m);if(delta){edge[i].w-=delta;edge[i^1].w+=delta;res+=delta;if(res==flow)break;}}}if(res!=flow)lev[u]=-1;return res;
}
void build(){ok[n]=1;for(int i=1;i<=l2;i++){int sz=ty[i].size();for(int j=0;j<sz;j++){int I=ty[i][j];if(!ok[I])continue;for(int k=0;k<j;k++){int J=ty[i][k];int K1=to[0][J],K2=to[1][J],K3=to[2][J];if(K1&&f[K1]+sz-k==f[I])add(J,K1),ok[K1]=1;if(K2&&f[K2]+sz-k==f[I])add(J,K2),ok[K2]=1;if(K3&&f[K3]+sz-k==f[I])add(J,K3),ok[K3]=1;}for(int k=j+1;k<sz;k++){int J=ty[i][k];int K1=to[0][J],K2=to[1][J],K3=to[2][J];if(K1&&f[K1]+k+1==f[I])add(J,K1),ok[K1]=1;if(K2&&f[K2]+k+1==f[I])add(J,K2),ok[K2]=1;if(K3&&f[K3]+k+1==f[I])add(J,K3),ok[K3]=1;}int K1=to[0][I],K2=to[1][I],K3=to[2][I];if(K1&&f[K1]+1==f[I])add(I,K1),ok[K1]=1;if(K2&&f[K2]+1==f[I])add(I,K2),ok[K2]=1;if(K3&&f[K3]+1==f[I])add(I,K3),ok[K3]=1;}}
}
void work2(){memset(head,-1,sizeof(head));cnt=-1;build();S=n+1,T=S+1;int ans=0;for(int i=1;i<=n;i++){if(du[i]>0)adde(S,i,du[i]),ans+=du[i];else if(du[i]<0)adde(i,T,-du[i]);}while(bfs(T))ans-=dinic(S,INF,T);printf("%d\n",ans);
}
int main(){n=read();for(int i=1;i<=n;i++){p[i].x=b[++l1]=read();p[i].y=c[++l2]=read();p[i].b1=d[++l3]=p[i].y-p[i].x;p[i].b2=e[++l4]=p[i].y+p[i].x;p[i].id=i;}p[++n].x=b[++l1]=0;p[n].y=c[++l2]=0;p[n].b1=d[++l3]=0;p[n].b2=e[++l4]=0;p[n].id=n;work1();work2();return 0;
}