2021.02.11

Author: seono

python/plat2/1067.py

@@ -0,0 +1,51 @@
+from cmath import exp, pi
+import sys
+input = sys.stdin.readline
+
+n = int(input())
+N = 1
+while N<2*n:N<<=1
+a = list(map(int,input().split()))+[0]*(N-n)
+b = list(map(int,input().split()))
+b.reverse()
+b = b+[0]*(N-2*n)+b
+# def fft(a):
+#     N = len(a)
+#     if N == 1: return a
+#     A_even = fft(a[0::2])
+#     A_odd = fft(a[1::2])
+#     w_N = [exp(2j*pi*n/N) for n in range(N//2)]
+#     return [A_even[n] + w_N[n] * A_odd[n] for n in range(N//2)] + \
+#         [A_even[n] - w_N[n] * A_odd[n] for n in range(N//2)]
+    
+def fft(x, inverse=False):
+    N, e = 1,0
+    while N < len(x):
+        N<<=1
+        e+=1
+    for i in range(N):
+        tmp = i
+        j = 0
+        for _ in range(e):
+            j=j<<1 | tmp&1
+            tmp>>=1
+        if i<j:x[i],x[j]=x[j],x[i]
+    n=2
+    while n<=N:
+        unit  = exp(2j*pi/n * (1 if inverse else -1))
+        for i in range(0,N,n):
+            W = 1
+            for k in range(i, i+n//2):
+                tmp = x[k+n//2]*W
+                x[k+n//2]=x[k]-tmp
+                x[k]+=tmp
+                W*=unit
+        n<<=1
+    if inverse:
+        for i in range(N):x[i]/=N
+
+fft(a)
+fft(b)
+s = [i*j for i, j in zip(a,b)]
+fft(s,True)
+print(max(int(round(x.real)) for x in s))

python/plat2/11495.py

@@ -0,0 +1,62 @@
+import sys
+from collections import defaultdict,deque
+input = sys.stdin.readline
+
+d = [(0,1),(0,-1),(1,0),(-1,0)]
+
+T = int(input())
+while T:
+    T-=1
+    n, m = map(int,input().split())
+    arr = []
+    for i in range(n):
+        arr+=[*map(int,input().split())]
+    max_n = n*m+2
+    cap = [[0]*max_n for _ in range(max_n)]
+    fl = [[0]*max_n for _ in range(max_n)]
+    adj = [[] for _ in range(max_n)]
+    S = max_n-2;E = max_n-1
+    for y in range(n):
+        for x in range(m):
+            now = y*m+x
+            if (y%2) ^ (x%2):
+                adj[now].append(E)
+                adj[E].append(now)
+                cap[now][E]=arr[now]
+            else:
+                adj[now].append(S)
+                adj[S].append(now)
+                cap[S][now]=arr[now]
+                for dy,dx in d:
+                    ny,nx= y+dy,x+dx
+                    if 0<=ny<n and 0<=nx<m:
+                        to = ny*m+nx
+                        adj[now].append(to)
+                        adj[to].append(now)
+                        cap[now][to]=arr[now]
+    ans = sum(arr)
+    while True:
+        visited = [-1]*max_n
+        q = deque()
+        q.append(S)
+        while q and visited[E]==-1:
+            n = q.popleft()
+            for nx in adj[n]:
+                if visited[nx]==-1 and cap[n][nx]>fl[n][nx]:
+                    visited[nx]=n
+                    q.append(nx)
+                    if nx==E:break
+        if visited[E]==-1:break
+        flow = 1e9
+        now = E
+        while now!=S:
+            flow = min(flow,cap[visited[now]][now] - fl[visited[now]][now])
+            now = visited[now]
+        now = E
+        while now!=S:
+            fl[visited[now]][now]+=flow
+            fl[now][visited[now]]-=flow
+            now = visited[now]
+        ans-=flow
+    print(ans)
+