結果
| 問題 |
No.1969 XOR Equation
|
| コンテスト | |
| ユーザー |
|
| 提出日時 | 2022-02-09 11:40:33 |
| 言語 | PyPy3 (7.3.15) |
| 結果 |
AC
|
| 実行時間 | 577 ms / 2,000 ms |
| コード長 | 2,844 bytes |
| コンパイル時間 | 232 ms |
| コンパイル使用メモリ | 82,108 KB |
| 実行使用メモリ | 92,536 KB |
| 最終ジャッジ日時 | 2024-09-21 03:29:17 |
| 合計ジャッジ時間 | 15,883 ms |
|
ジャッジサーバーID (参考情報) |
judge2 / judge4 |
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| ファイルパターン | 結果 |
|---|---|
| sample | AC * 1 |
| other | AC * 36 |
ソースコード
def solve_mini(N,A,Y,M=60):
dp = [[1<<(M+1) for j in range(N+1)] for i in range(M+1)]
for j in range(Y>>M,N+1,2):
dp[M][j] = 0
low_sort = [[i for i in range(N)] for _ in range(M)]
for t in range(M):
low_sort[t].sort(key=lambda i:A[i]%(1<<(t+1)),reverse=True)
"""
pre = [i for i in range(N)]
for t in range(M):
zero,one = [],[]
for i in pre:
if A[i]>>t & 1:
one.append(i)
else:
zero.append(i)
pre = one + zero
low_sort[t] = [i for i in pre]
"""
for i in range(M)[::-1]:
zero,one,two = 0,0,0
for j in range(N):
if A[j]>>i & 1:
one += 1
else:
zero += 1
if one&1==(Y>>i & 1):
dp[i][0] = min(dp[i][0], 2*dp[i+1][two])
if (zero+two)&1==(Y>>i & 1):
dp[i][0] = min(dp[i][0], 2*dp[i+1][one+two]+1)
if i==0:
break
for j in range(1,N+1):
next_up = low_sort[i-1][j-1]
if A[next_up]>>i & 1:
one -= 1
two += 1
else:
zero -= 1
one += 1
if j!=N:
next_next_up = low_sort[i-1][j]
if A[next_up]%(1<<(t+1)) == A[next_next_up]%(1<<(t+1)):
continue
if one&1==(Y>>i & 1):
dp[i][j] = min(dp[i][j], 2*dp[i+1][two])
if (zero+two)&1==(Y>>i & 1):
dp[i][j] = min(dp[i][j], 2*dp[i+1][one+two]+1)
if dp[0][0]==1<<(M+1):
return -1
return dp[0][0]
def brute(N,A,Y):
ans = 2**61
def dfs(d,tmp,up):
nonlocal ans
if d==61:
if len(up)&1==0:
return tmp
else:
return 1<<61
res = ans
if tmp > res:
return ans
zero,one,two = 0,set(),set()
for i in range(N):
if A[i]>>d & 1:
if i in up:
two.add(i)
else:
one.add(i)
else:
if i in up:
one.add(i)
else:
zero += 1
if len(one)&1==(Y>>d)&1:
res = min(res,dfs(d+1,tmp,two))
if (zero+len(two))&1==(Y>>d)&1 and res > tmp + (1<<d):
n_up = set([i for i in one]+[j for j in two])
res = min(res,dfs(d+1,tmp+(1<<d),n_up))
ans = min(ans,res)
return res
res = dfs(0,0,set())
if res < 2**61:
return res
return -1
for _ in range(int(input())):
N,Y = map(int,input().split())
A = list(map(int,input().split()))
print(solve_mini(N,A,Y))