#include <stdio.h>#include <string.h>#include <iostream>#include <vector>#define maxn 52using namespace std;vector<int> a[maxn];int n,m,no;int f[maxn][maxn];int id[maxn*maxn];bool vis[maxn];void DFS(int u){ vis[u]=1; int v; for(int i=0;i<a[u].size();i++){ v=a[u][i]; if(!vis[v]){ id[f[u][v]]=++no; DFS(v); } else if(!id[f[u][v]]) id[f[u][v]]=++no; }}int main(){ cin>>n>>m; no=0; memset(vis,0,sizeof(vis)); memset(id,0,sizeof(id)); int x,y; for(int i=1;i<=m;i++){ scanf("%d%d",&x,&y); a[x].push_back(y); a[y].push_back(x); f[x][y]=f[y][x]=i; } for(int i=1;i<=n;i++) if(!vis[i]) DFS(i); printf("YESn"); for(int i=1;i<m;i++) printf("%d ",id[i]); printf("%dn",id[m]); return 0;}
