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#include<cstdio>
#include<cstring>
#include<algorithm>
#include<iostream>
#include<queue>
#include<map>
#include<stack>
#include<cmath>
#include<set>
#include<bitset>
#include<assert.h>
#define inc(i,l,r) for(int i=l;i<=r;i++)
#define dec(i,l,r) for(int i=l;i>=r;i--)
#define link(x) for(edge *j=h[x];j;j=j->next)
#define mem(a) memset(a,0,sizeof(a))
#define ll long long
#define eps 1e-8
#define succ(x) (1<<x)
#define lowbit(x) (x&(-x))
#define sqr(x) ((x)*(x))
#define mid (x+y>>1)
#define NM 105
#define nm 200005
#define pi 3.1415926535897931
#define mp(x,y) make_pair(x,y)
using namespace std;
const int inf=1e9;
ll read(){
ll x=0,f=1;char ch=getchar();
while(!isdigit(ch)){if(ch=='-')f=-1;ch=getchar();}
while(isdigit(ch))x=x*10+ch-'0',ch=getchar();
return f*x;
}
int n,_x,_y,_ans;
bool a[NM][NM];
bool _v[NM],__v[NM],V[NM];
int v[NM],match[NM],ans,_match[NM];
bool dfs(int x){
inc(j,1,n)if(V[j]&&a[x][j]&&v[j]!=_x){
v[j]=_x;
if(!match[j]||dfs(match[j])){match[j]=x;return true;}
}
return false;
}
void _dfs(int x){
__v[x]++;
inc(j,1,n)if(a[x][j]&&!_v[j]){
_v[j]++;
_dfs(match[j]);
}
}
int main(){
n=read();int _=read();while(_--){
_x=read();_y=read();a[_x][_y]++;
}
inc(k,1,n)inc(i,1,n)if(i!=k&&a[i][k])inc(j,1,n)if(i!=j&&k!=j&&a[k][j])a[i][j]=true;
ans=n;
inc(i,1,n)V[i]=true;
inc(i,1,n)if(dfs(_x=i))ans--;
inc(i,1,n)_match[match[i]]=i;
printf("%d\n",ans);
_ans=ans;
inc(i,1,n)if(!_match[i])_dfs(i);
inc(i,1,n)if(__v[i]&&!_v[i])putchar('1');else putchar('0');putchar('\n');
inc(k,1,n){
inc(i,1,n)if(a[i][k]||a[k][i])V[i]=false;else V[i]=true;
V[k]=false;
ans=0;
inc(i,1,n)if(V[i])ans++;
mem(v);mem(match);
inc(i,1,n)if(V[i]&&dfs(_x=i))ans--;
if(ans+1==_ans)putchar('1');else putchar('0');
}
putchar('\n');
return 0;
}
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