結果
| 問題 |
No.1288 yuki collection
|
| コンテスト | |
| ユーザー |
|
| 提出日時 | 2022-04-13 23:33:32 |
| 言語 | PyPy3 (7.3.15) |
| 結果 |
WA
|
| 実行時間 | - |
| コード長 | 2,891 bytes |
| コンパイル時間 | 290 ms |
| コンパイル使用メモリ | 82,816 KB |
| 実行使用メモリ | 95,052 KB |
| 最終ジャッジ日時 | 2024-12-24 00:13:49 |
| 合計ジャッジ時間 | 32,194 ms |
|
ジャッジサーバーID (参考情報) |
judge5 / judge3 |
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| ファイルパターン | 結果 |
|---|---|
| sample | AC * 3 |
| other | AC * 35 WA * 5 |
ソースコード
#その2 最初はコストが全部正の場合に使えるダイクストラ
from heapq import heappush,heappop
class MinCostFlow:
inf = 10 ** 18
def __init__(self,N):
self.N = N
self.G = [[] for _ in range(N)]
self.H = [0] * N
self.edge = []
def add_edge(self,fr,to,cap,cost):
e = [to,cap,cost,None]
r = e[3] = [fr,0,-cost,e]
self.G[fr].append(e)
self.G[to].append(r)
self.edge.append(e)
def get_edge(self,i):
return self.edge[i]
def flow(self,s,t,f):
N = self.N
G = self.G
inf = MinCostFlow.inf
res = 0
H = self.H #ポテンシャル、コストが最初は正なので、最初は0でいい
prev_v = [0] * N
prev_e = [None] * N
d0 = [inf] * N
dist = [inf] * N
while f:
dist[:] = d0
dist[s] = 0
q = [(0,s)]
while q:
c,v = heappop(q)
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]
prev_v[w] = v
prev_e[w] = e
heappush(q,(r,w))
if dist[t] == inf:
return None
"""
for i in range(N):
H[i] += dist[i]
"""
H = [h + d for h,d in zip(H,dist)]
d = f
v = t
while v != s:
d = min(d,prev_e[v][1])
v = prev_v[v]
f -= d
res += d * H[t]
v = t
while v != s:
e = prev_e[v]
e[1] -= d
e[3][1] += d
v = prev_v[v]
return res
N = int(input())
S = input()
V = list(map(int,input().split()))
d = {"y":0,"u":1,"k":2,"i":3}
dat = [[] for _ in range(4)]
for i in range(N):
dat[d[S[i]]].append(i)
s = 0
t = N + 1
inf = 10 ** 10
mincost = MinCostFlow(N + 2)
"""
for x in dat[0]:
mincost.add_edge(s,x + 1,inf,0)
"""
if dat[0]:
mincost.add_edge(s,dat[0][0]+1,inf,0)
for x in dat[-1]:
mincost.add_edge(x + 1,t,1,inf - V[x])
for i in range(3):
a = dat[i]
b = dat[i+1]
right = 0
for left in range(len(a)):
while right < len(b) and b[right] < a[left]:
right += 1
if right < len(b):
mincost.add_edge(a[left] + 1,b[right] + 1,1,inf - V[a[left]])
for i in range(4):
a = dat[i]
for j in range(len(a) - 1):
mincost.add_edge(a[j] + 1,a[j+1] + 1,inf,0)
ans = 0
while True:
tmp = mincost.flow(s,t,1)
if tmp is None:
break
tmp = 4 * inf - tmp
#print(tmp)
ans += tmp
print(ans)
#print(dat)