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| #include <iostream> #include <cstdio> #include <queue> #include <climits> #define inf INT_MAX using namespace std; const int N = 410, M = 5e4 + 10; bool vis[N]; int n, m, st, ed, day, path, d[N], pre[N], incf[N]; int idx = -1, hd[N], nxt[M], edg[M], wt[M], f[M]; bool spfa() { for (int i = st; i <= ed; i++) incf[i] = 0; for (int i = st; i <= ed; i++) d[i] = inf; incf[st] = inf; d[st] = 0; queue <int> q; q.push(st); vis[st] = true; while (!q.empty()) { int t = q.front(); q.pop(); vis[t] = false; for (int i = hd[t]; ~i; i = nxt[i]) if (d[t] + f[i] < d[edg[i]] && wt[i]) { d[edg[i]] = d[t] + f[i]; pre[edg[i]] = i; incf[edg[i]] = min(wt[i], incf[t]); if (!vis[edg[i]]) { vis[edg[i]] = true; q.push(edg[i]); } } } return incf[ed] > 0; } void ek() { while (spfa()) { int t = incf[ed]; day += t; path += t * d[ed]; for (int i = ed; i != st; i = edg[pre[i] ^ 1]) { wt[pre[i]] -= t; wt[pre[i] ^ 1] += t; } } } void add(int a, int b, int c, int d) { nxt[++idx] = hd[a]; hd[a] = idx; edg[idx] = b; wt[idx] = c; f[idx] = d; } int main() { cin >> n >> m; st = 0; ed = n << 1 | 1; for (int i = st; i <= ed; i++) hd[i] = -1; add(st, 1, inf, 0); add(1, st, 0, 0); for (int i = 1, a, b, c; i <= m; i++) { cin >> a >> b >> c; add(a, b + n, 1, c); add(b + n, a, 0, -c); } for (int i = 2; i <= n; i++) { add(i + n, i, 1, 0); add(i, i + n, 0, 0); } add(n << 1, ed, inf, 0); add(ed, n << 1, 0, 0); ek(); cout << day << ' ' << path; return 0; }
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