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- #include <bits/stdc++.h>
- #define fi first
- #define se second
- #define rep(i,n) for(int i = 0; i < (n); ++i)
- #define rrep(i,n) for(int i = 1; i <= (n); ++i)
- #define drep(i,n) for(int i = (n)-1; i >= 0; --i)
- #define srep(i,s,t) for (int i = s; i < t; ++i)
- #define rng(a) a.begin(),a.end()
- #define rrng(a) a.rbegin(),a.rend()
- #define maxs(x,y) (x = max(x,y))
- #define mins(x,y) (x = min(x,y))
- #define limit(x,l,r) max(l,min(x,r))
- #define lims(x,l,r) (x = max(l,min(x,r)))
- #define isin(x,l,r) ((l) <= (x) && (x) < (r))
- #define pb push_back
- #define sz(x) (int)(x).size()
- #define pcnt __builtin_popcountll
- #define uni(x) x.erase(unique(rng(x)),x.end())
- #define snuke srand((unsigned)clock()+(unsigned)time(NULL));
- #define show(x) cout<<#x<<" = "<<x<<endl;
- #define PQ(T) priority_queue<T,v(T),greater<T> >
- #define bn(x) ((1<<x)-1)
- #define dup(x,y) (((x)+(y)-1)/(y))
- #define newline puts("")
- #define v(T) vector<T>
- #define vv(T) v(v(T))
- using namespace std;
- typedef long long int ll;
- typedef unsigned uint;
- typedef unsigned long long ull;
- typedef pair<int,int> P;
- typedef vector<int> vi;
- typedef vector<vi> vvi;
- typedef vector<ll> vl;
- typedef vector<P> vp;
- inline int in() { int x; scanf("%d",&x); return x;}
- template<typename T>inline istream& operator>>(istream&i,v(T)&v)
- {rep(j,sz(v))i>>v[j];return i;}
- template<typename T>string join(const v(T)&v)
- {stringstream s;rep(i,sz(v))s<<' '<<v[i];return s.str().substr(1);}
- template<typename T>inline ostream& operator<<(ostream&o,const v(T)&v)
- {if(sz(v))o<<join(v);return o;}
- template<typename T1,typename T2>inline istream& operator>>(istream&i,pair<T1,T2>&v)
- {return i>>v.fi>>v.se;}
- template<typename T1,typename T2>inline ostream& operator<<(ostream&o,const pair<T1,T2>&v)
- {return o<<v.fi<<","<<v.se;}
- template<typename T>inline ll suma(const v(T)& a) { ll res(0); for (auto&& x : a) res += x; return res;}
- const double eps = 1e-10;
- const ll LINF = 1001002003004005006ll;
- const int INF = 1001001001;
- #define dame { puts("-1"); return 0;}
- #define yn {puts("YES");}else{puts("NO");}
- const int MX = 200005;
- // Max flow
- // !! Be care of double and INF !!
- struct Maxflow {
- typedef int TT;
- int n;
- vi to, next, head, dist, it;
- vector<TT> lim;
- Maxflow(){}
- Maxflow(int n):n(n),head(n,-1),it(n){}
- void add(int a, int b, TT c=1) {
- next.pb(head[a]); head[a] = sz(to); to.pb(b); lim.pb(c);
- next.pb(head[b]); head[b] = sz(to); to.pb(a); lim.pb(0);
- }
- // void add2(int a, int b, int c=1) {
- // next.pb(head[a]); head[a] = sz(to); to.pb(b); lim.pb(c);
- // next.pb(head[b]); head[b] = sz(to); to.pb(a); lim.pb(c);
- // }
- void bfs(int sv) {
- dist = vi(n,INF);
- queue<int> q;
- dist[sv] = 0; q.push(sv);
- while (!q.empty()){
- int v = q.front(); q.pop();
- for (int i = head[v]; i != -1; i = next[i]) {
- if (lim[i] && dist[to[i]] == INF) { // double INF !!
- dist[to[i]] = dist[v]+1; q.push(to[i]);
- }
- }
- }
- }
- TT dfs(int v, int tv, TT nf=INF) { // INF !!
- if (v == tv) return nf;
- for (; it[v] != -1; it[v] = next[it[v]]) {
- int u = to[it[v]]; TT f;
- if (!lim[it[v]] || dist[v] >= dist[u]) continue;
- if (f = dfs(u, tv, min(nf, lim[it[v]])), f) { // double !!
- lim[it[v]] -= f;
- lim[it[v]^1] += f;
- return f;
- }
- }
- return 0;
- }
- TT solve(int sv, int tv) {
- TT flow = 0, f;
- while (1) {
- bfs(sv);
- if (dist[tv] == INF) return flow;
- rep(i,n) it[i] = head[i];
- while (f = dfs(sv,tv), f) flow += f;
- }
- }
- };
- //
- int n;
- vvi to;
- vi ans;
- map<P,int> mp;
- int dfs(int v) {
- int r = v<n?n-1:-n;
- for (int u : to[v]) {
- int x = dfs(u);
- // cerr<<v<<" "<<u<<" "<<x<<endl;
- if (v < n) ans[mp[P(v,u-n)]] = abs(x);
- else ans[mp[P(u,v-n)]] = abs(x);
- r += x;
- }
- return r;
- }
- int main() {
- int m;
- scanf("%d%d",&n,&m);
- int sv = n+(n-1), tv = sv+1;
- Maxflow g(tv+1);
- vp es;
- vvi ato(n);
- rep(i,m) {
- int a,b;
- scanf("%d%d",&a,&b);
- --a; --b;
- swap(a,b);
- es.pb(P(a,b));
- mp[P(a,b)] = i;
- g.add(a,n+b);
- ato[a].pb(b);
- }
- rep(i,n) g.add(sv,i);
- rep(i,n-1) g.add(n+i,tv);
- if (g.solve(sv,tv) != n-1) dame;
- to = vvi(sv);
- vi p(n-1);
- vi pp(n,-1);
- rep(i,m) {
- int e = i<<1;
- if (!g.lim[e]) {
- int a = es[i].fi, b = es[i].se;
- to[n+b].pb(a);
- p[b] = a;
- pp[a] = b;
- }
- }
- int root = -1;
- rep(i,n) if (pp[i] == -1) root = i;
- vi p2(n-1,-1);
- {
- queue<int> q;
- for (int b : ato[root]) {
- if (p2[b] != -1) continue;
- p2[b] = root;
- q.push(b);
- }
- while (sz(q)) {
- int v = q.front(); q.pop();
- v = p[v];
- for (int b : ato[v]) {
- if (p2[b] != -1) continue;
- p2[b] = v;
- q.push(b);
- }
- }
- rep(i,n-1) {
- if (p2[i] == -1) dame;
- to[p2[i]].pb(n+i);
- }
- }
- ans = vi(m);
- dfs(root);
- for (int x : ans) printf("%d\n",x);
- return 0;
- }
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