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IDProblemSubmitterResultTimeMemoryLanguageFile sizeSubmit timeJudge time
#97672#6329. Colorful Graphyzc2005WA 1ms4092kbC++144.0kb2023-04-17 21:07:392023-04-17 21:07:39

Judging History

你现在查看的是最新测评结果

  • [2023-08-10 23:21:45]
  • System Update: QOJ starts to keep a history of the judgings of all the submissions.
  • [2023-04-17 21:07:39]
  • 评测
  • 测评结果:WA
  • 用时:1ms
  • 内存:4092kb
  • [2023-04-17 21:07:39]
  • 提交

answer

#include <bits/stdc++.h>
using namespace std;
mt19937_64 rnd(chrono::steady_clock::now().time_since_epoch().count());
using pii = pair<int, int>;
using i64 = long long;
#define rep(i, a, b) for (int i = a, I = b; i <= I; ++i)
#define per(i, a, b) for (int i = a, I = b; i >= I; --i)
template<typename T> void up(T &x, T y) { if (x < y) x = y; }
template<typename T> void down(T &x, T y) { if (x > y) x = y; }

const int N = 7005, inf = 1e9;
int n, m, a[N], b[N], c[N], bel[N], stk[N], to[N], top, cnt, d[N];
vector<int> e1[N], e2[N];
bool vis[N];

void dfs1(int u) {
    vis[u] = 1;
    for (auto v : e2[u]) if (!vis[v]) dfs1(v);
    stk[++top] = u;
}
void dfs2(int u, int c) {
    bel[u] = c;
    for (auto v : e1[u]) if (!bel[v]) dfs2(v, c);
}

vector<int> A, B;
namespace flow {
	const int N = 14005, M = 123456;
	int n, s, t, d[N], que[N], cap[M], res;
	int cnt = 1, head[N], cur[N], to[M], nxt[M], val[M];

	void addedge(int u, int v, int w) {
		to[++cnt] = v;
        cap[cnt] = val[cnt] = w;
		nxt[cnt] = head[u];
		head[u] = cnt;
	}
	void add(int u, int v, int w) {
		addedge(u, v, w);
		addedge(v, u, 0); 
	}
	bool bfs() {
		int l = 1, r = 0;
		rep(i, 0, n) cur[i] = head[i], d[i] = 0;
		que[++r] = s, d[s] = 1;
		while (l <= r) {
			int u = que[l++];
			for (int i = head[u]; i; i = nxt[i]) {
				int v = to[i], w = val[i];
				if (d[v] || !w) continue;
				d[v] = d[u] + 1;
				que[++r] = v;
			}
		} 
		return d[t];
	}
	int dfs(int u, int flow) {
		if (u == t) return flow;
		int rest = flow;
		for (int &i = cur[u]; i; i = nxt[i]) {
			int v = to[i], w = val[i];
			if (d[v] != d[u] + 1 || !w) continue;
			int k = dfs(v, min(flow, w));
			if (!k) d[v] = 0;
			rest -= k;
			val[i] -= k, val[i ^ 1] += k; 
			if (!rest) break;
		}
		return flow - rest;
	}
	int dinic() {
		res = 0;
		while (bfs()) res += dfs(s, inf); 
		return res;
	}

    struct edge {
        int to, nxt, val;
    } e[M];
    int hd[N], tot;
    // void get_path(int u) {
        // for (int &i = hd[u]; i; ) {
        //     int v = e[i].to;
        //     if (!--e[i].val) i = e[i].nxt;
        //     get_path(v);
        //     if (v == t) B.push_back(u);
        //     if (u == s) A.push_back(v);
        // }
    // }
    void get_path(int u) {
        for (int &i = hd[u]; i; ) {
            int v = e[i].to;
            if (!--e[i].val) i = e[i].nxt;
            if (v == t) B.push_back(u);
            if (u == s) A.push_back(v);
            get_path(v);
            return;
        }
    }
    void solve() {
        rep(u, 0, n) {
            for (int i = head[u]; i; i = nxt[i]) {
                if (!cap[i]) continue;
                int f = cap[i] - val[i];
                if (!f) continue;
                int v = to[i];
                e[++tot] = {v, hd[u], f}, hd[u] = tot;
            }
        }
        while (res--) get_path(s);
        // get_path(s);
    }
}

int main() {
    freopen("1.in", "r", stdin);
    ios::sync_with_stdio(0), cin.tie(0);

    cin >> n >> m;
    rep(i, 1, m) {
        cin >> a[i] >> b[i];
        e1[a[i]].push_back(b[i]);
        e2[b[i]].push_back(a[i]);
    }
    rep(i, 1, n) if (!vis[i]) dfs1(i);
    per(i, n, 1) {
        int u = stk[i];
        if (!bel[u]) dfs2(u, ++cnt);
    }
    
    flow::t = flow::n = 2 * cnt + 1;
    rep(i, 1, cnt) flow::add(flow::s, i, 1), flow::add(i + cnt, flow::t, 1);
    rep(i, 1, cnt) flow::add(i + cnt, i, inf);
    rep(i, 1, m) {
        int u = bel[a[i]], v = bel[b[i]];
        if (u == v) continue;
        flow::add(u, v + cnt, inf);
    }

    int res = flow::dinic();
    flow::solve();
    assert((int) A.size() == res);
    rep(i, 0, res - 1) {
        to[A[i]] = B[i] - cnt, ++d[B[i] - cnt];
        assert(d[B[i] - cnt] == 1);
    }
    int col = 0;
    rep(u, 1, cnt) {
        if (d[u]) continue;
        c[u] = ++col;
        int x = u;
        while (to[x]) x = to[x], c[x] = col;
    }
    rep(i, 1, n) cout << c[bel[i]] << " \n"[i == n];

    return 0;
}

Details

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Test #1:

score: 0
Wrong Answer
time: 1ms
memory: 4092kb

input:

5 5
1 4
2 3
1 3
2 5
5 1

output:


result:

wrong output format Unexpected end of file - int32 expected