51 lines
1.3 KiB
C++
51 lines
1.3 KiB
C++
// P5960：求任意一组差分约束可行解。C++11。
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#include <iostream>
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#include <vector>
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#include <queue>
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using namespace std;
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using ll = long long;
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struct Edge { int v, w; };
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bool solve(const vector<vector<Edge>>& g, vector<ll>& dis) {
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int n = static_cast<int>(g.size()) - 1;
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dis.assign(n + 1, 0);
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vector<int> len(n + 1, 0);
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vector<bool> inq(n + 1, true);
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queue<int> q;
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for (int i = 1; i <= n; ++i) q.push(i);
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while (!q.empty()) {
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int u = q.front(); q.pop();
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inq[u] = false;
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for (auto e : g[u]) {
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int v = e.v;
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ll nd = dis[u] + e.w;
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if (nd >= dis[v]) continue;
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dis[v] = nd;
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len[v] = len[u] + 1;
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if (len[v] >= n) return false;
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if (!inq[v]) {
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q.push(v); inq[v] = true;
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}
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}
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}
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return true;
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}
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int main() {
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ios::sync_with_stdio(false);
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cin.tie(nullptr);
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int n, m;
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if (!(cin >> n >> m)) return 0;
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vector<vector<Edge>> g(n + 1);
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for (int i = 0; i < m; ++i) {
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int a, b, w; cin >> a >> b >> w;
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g[b].push_back({a, w});
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}
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vector<ll> dis;
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if (!solve(g, dis)) cout << "NO\n";
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else {
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for (int i = 1; i <= n; ++i)
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cout << dis[i] << (i == n ? '\n' : ' ');
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}
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}
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