結果

問題 No.1301 Strange Graph Shortest Path
ユーザー 👑 rin204rin204
提出日時 2022-11-02 16:21:09
言語 PyPy3
(7.3.15)
結果
AC  
実行時間 1,271 ms / 3,000 ms
コード長 1,864 bytes
コンパイル時間 287 ms
コンパイル使用メモリ 82,048 KB
実行使用メモリ 211,524 KB
最終ジャッジ日時 2024-07-17 05:37:27
合計ジャッジ時間 36,733 ms
ジャッジサーバーID
(参考情報)
judge1 / judge2
このコードへのチャレンジ
(要ログイン)

テストケース

テストケース表示
入力 結果 実行時間
実行使用メモリ
testcase_00 AC 38 ms
52,352 KB
testcase_01 AC 41 ms
52,608 KB
testcase_02 AC 1,045 ms
200,916 KB
testcase_03 AC 993 ms
186,792 KB
testcase_04 AC 1,185 ms
205,284 KB
testcase_05 AC 1,052 ms
203,660 KB
testcase_06 AC 1,050 ms
195,444 KB
testcase_07 AC 1,089 ms
197,604 KB
testcase_08 AC 1,034 ms
188,284 KB
testcase_09 AC 988 ms
189,148 KB
testcase_10 AC 962 ms
188,096 KB
testcase_11 AC 1,271 ms
199,688 KB
testcase_12 AC 1,117 ms
199,628 KB
testcase_13 AC 1,078 ms
202,000 KB
testcase_14 AC 1,016 ms
188,740 KB
testcase_15 AC 1,057 ms
191,248 KB
testcase_16 AC 1,168 ms
205,492 KB
testcase_17 AC 1,102 ms
203,976 KB
testcase_18 AC 1,178 ms
192,836 KB
testcase_19 AC 1,098 ms
196,200 KB
testcase_20 AC 1,046 ms
193,468 KB
testcase_21 AC 1,060 ms
201,212 KB
testcase_22 AC 1,157 ms
196,708 KB
testcase_23 AC 1,028 ms
202,240 KB
testcase_24 AC 1,084 ms
195,112 KB
testcase_25 AC 1,185 ms
205,208 KB
testcase_26 AC 1,071 ms
196,756 KB
testcase_27 AC 1,124 ms
198,856 KB
testcase_28 AC 936 ms
197,200 KB
testcase_29 AC 1,116 ms
203,900 KB
testcase_30 AC 1,246 ms
204,692 KB
testcase_31 AC 1,142 ms
203,668 KB
testcase_32 AC 41 ms
52,736 KB
testcase_33 AC 514 ms
194,176 KB
testcase_34 AC 1,210 ms
211,524 KB
権限があれば一括ダウンロードができます

ソースコード

diff #

from heapq import heappush, heappop
class MinCostFlow:
    INF = 10**18

    def __init__(self, N):
        self.N = N
        self.G = [[] for i in range(N)]

    def add_edge(self, fr, to, cap, cost):
        forward = [to, cap, cost, None]
        backward = forward[3] = [fr, 0, -cost, forward]
        self.G[fr].append(forward)
        self.G[to].append(backward)

    def flow(self, s, t, f):
        N = self.N; G = self.G
        INF = MinCostFlow.INF

        res = 0
        H = [0]*N
        prv_v = [0]*N
        prv_e = [None]*N

        d0 = [INF]*N
        dist = [INF]*N

        while f:
            dist[:] = d0
            dist[s] = 0
            que = [(0, s)]

            while que:
                c, v = heappop(que)
                if dist[v] < c:
                    continue
                r0 = dist[v] + H[v]
                for e in G[v]:
                    w, cap, cost, _ = e
                    if cap > 0 and r0 + cost - H[w] < dist[w]:
                        dist[w] = r = r0 + cost - H[w]
                        prv_v[w] = v; prv_e[w] = e
                        heappush(que, (r, w))
            if dist[t] == INF:
                return None

            for i in range(N):
                H[i] += dist[i]

            d = f; v = t
            while v != s:
                d = min(d, prv_e[v][1])
                v = prv_v[v]
            f -= d
            res += d * H[t]
            v = t
            while v != s:
                e = prv_e[v]
                e[1] -= d
                e[3][1] += d
                v = prv_v[v]
        return res

n, m = map(int, input().split())
G = MinCostFlow(n)
for _ in range(m):
    u, v, c, d = map(int, input().split())
    u -= 1
    v -= 1
    G.add_edge(u, v, 1, c)
    G.add_edge(v, u, 1, c)
    G.add_edge(u, v, 1, d)
    G.add_edge(v, u, 1, d)

print(G.flow(0, n - 1, 2))
0