Problem:


Score : 400 points

Problem Statement

A maze is composed of a grid of H \times W squares - H vertical, W horizontal.

The square at the i-th row from the top and the j-th column from the left - (i,j) - is a wall if S_{ij} is # and a road if S_{ij} is ..

There is a magician in (C_h,C_w). He can do the following two kinds of moves:

Move A: Walk to a road square that is vertically or horizontally adjacent to the square he is currently in.

Move B: Use magic to warp himself to a road square in the 5\times 5 area centered at the square he is currently in.

In either case, he cannot go out of the maze.

At least how many times does he need to use the magic to reach (D_h, D_w)?

Constraints

1 \leq H,W \leq 10^3

1 \leq C_h,D_h \leq H

1 \leq C_w,D_w \leq W

S_{ij} is # or ..

S_{C_h C_w} and S_{D_h D_w} are ..

(C_h,C_w) \neq (D_h,D_w)

Input

Input is given from Standard Input in the following format:

H W
C_h C_w
D_h D_w
S_{11}\ldots S_{1W}
\vdots
S_{H1}\ldots S_{HW}

Output

Print the minimum number of times the magician needs to use the magic. If he cannot reach (D_h,D_w), print -1 instead.

Sample Input 1

4 4
1 1
4 4
..#.
..#.
.#..
.#..

Sample Output 1

1

For example, by walking to (2,2) and then using the magic to travel to (4,4), just one use of magic is enough.

Note that he cannot walk diagonally.

Sample Input 2

4 4
1 4
4 1
.##.
####
####
.##.

Sample Output 2

-1

He cannot move from there.

Sample Input 3

4 4
2 2
3 3
....
....
....
....

Sample Output 3

0

No use of magic is needed.

Sample Input 4

4 5
1 2
2 5
#.###
####.
#..##
#..##

Sample Output 4

2



Sample input:
4 4
1 1
4 4
..#.
..#.
.#..
.#..


Sample output:
1

Submission status: Accepted

Solution code:
#!/usr/bin/env python3

import sys
import math
from bisect import bisect_right as br
from bisect import bisect_left as bl
sys.setrecursionlimit(2147483647)
from heapq import heappush, heappop,heappushpop
from collections import defaultdict
from itertools import accumulate
from collections import Counter
from collections import deque
from operator import itemgetter
from itertools import permutations
mod = 10**9 + 7
inf = float('inf')
def I(): return int(sys.stdin.readline())
def LI(): return list(map(int,sys.stdin.readline().split()))

h, w = LI()
ch, cw = LI()
dh, dw = LI()
s = [input() for _ in range(h)]

dx, dy = [1, 0, -1, 0], [0, 1, 0, -1]
que = deque([(cw-1, ch-1)])
d = [[10**10] * w for _ in range(h)]
d[ch-1][cw-1] = 0
while que:
    x, y = que.popleft()
    for i in range(4):
        nx, ny = x + dx[i], y + dy[i]
        if 0 <= nx < w and 0 <= ny < h:
            if s[ny][nx] == '.' and d[ny][nx] > d[y][x]:
                d[ny][nx] = d[y][x]
                que.appendleft((nx, ny))
    for i in range(-2, 3):
        for j in range(-2, 3):
            nx, ny = x + i, y + j
            if 0 <= nx < w and 0 <= ny < h:
                if s[ny][nx] == '.' and d[ny][nx] > d[y][x] + 1:
                    d[ny][nx] = d[y][x] + 1
                    que.append((nx, ny))
if d[dh-1][dw-1] == 10**10:
    print(-1)
else:
    print(d[dh-1][dw-1])

Submission status: Accepted

Solution code:
import sys
input = lambda : sys.stdin.readline().rstrip()
sys.setrecursionlimit(max(1000, 10**9))
write = lambda x: sys.stdout.write(x+"\n")


import numpy as np
from numba import njit, b1, i4, i8, f8
from heapq import heappop as hpp, heappush as hp

h,w = map(int, input().split())
ch,cw = map(int, input().split())
dh,dw = map(int, input().split())
ch -= 1
cw -= 1
dh -= 1
dw -= 1
rows,cols = h,w

OK = "."
NG = "#"

ss = np.array([[c=="#" for c in input()] for _ in range(h)])
@njit((b1[:, :],i8,i8,i8,i8), cache=True)
def main(ss,ch,cw,dh,dw):
    inf = 1<<30
    start = ch*w+cw
    goal = dh*w+dw
    n = h*w
    seen = np.full(n, inf, np.int64)
    seen[start] = 0
    q = [(0, start)] # ワープ回数, 現在位置, 最後の道の位置
    # dx = [0,1,0,-1]
    # dy = [1,0,-1,0]
    dx = []
    dy = []
    vvs = []
    for i in range(-2,3):
        for j in range(-2,3):
            if not (i==j==0):
                dx.append(i)
                dy.append(j)
                if abs(i)+abs(j)>1:
                    vvs.append(1)
                else:
                    vvs.append(0)
    while q:
#         print(seen)
        pnum,pu = hpp(q)
        ux,uy = divmod(pu,w)
        # print(pnum,divmod(pu,w))
        if pu==goal:
            break
        for xx,yy,vv in zip(dx,dy,vvs):
    #         x = ux+xx
    #         y = uy+yy
            x,y = ux+xx, uy+yy
            u = x*w + y
            num = pnum+vv
            if x<0 or y<0 or x>=h or y>=w or ss[x][y]:
                continue
    #         print(x,y)
            if seen[u]>num:
                seen[u] = num
                hp(q,(num, u))
                
    val = seen[goal]
    if val==inf:
        return -1
    else:
        return val
print(main(ss,ch,cw,dh,dw))

Submission status: Accepted

Solution code:
from collections import deque

h, w = (int(x) for x in input().split())
ch, cw = (int(x) - 1 for x in input().split())
dh, dw = (int(x) - 1 for x in input().split())
s = [list(input()) for _ in range(h)]
d = [[-1] * w for _ in range(h)]
d[ch][cw] = 0
walk = [[0, 1], [0, -1], [1, 0], [-1, 0]]
warp = [[2, 2], [2, 1], [2, 0], [2, -1], [2, -2], [1, 2], [1, 1], [1, -1], [1, -2], [0, 2], [0, -2], [-1, 2], [-1, 1],
     [-1, -1], [-1, -2], [-2, 2], [-2, 1], [-2, 0], [-2, -1], [-2, -2]]

que = deque([(0, ch, cw)])
while que:
    count, y, x = que.popleft()
    if d[y][x] < count:
        continue
    for NY, NX in walk:
        if 0 <= y + NY < h and 0 <= x + NX < w and s[y + NY][x + NX] != '#':
            if d[y + NY][x + NX] == -1 or d[y + NY][x + NX] > count:
                d[y + NY][x + NX] = count
                que.appendleft((count, y + NY, x + NX))
    for NY, NX in warp:
        if 0 <= y + NY < h and 0 <= x + NX < w and s[y + NY][x + NX] != '#':
            if d[y + NY][x + NX] == -1 or d[y + NY][x + NX] > count + 1:
                d[y + NY][x + NX] = count + 1
                que.append((count + 1, y + NY, x + NX))

print(d[dh][dw])

Submission status: Accepted

Solution code:
import sys
input = lambda : sys.stdin.readline().rstrip()
sys.setrecursionlimit(max(1000, 10**9))
write = lambda x: sys.stdout.write(x+"\n")


import numpy as np
from numba import njit, b1, i4, i8, f8
from heapq import heappop as hpp, heappush as hp

h,w = map(int, input().split())
ch,cw = map(int, input().split())
dh,dw = map(int, input().split())
ch -= 1
cw -= 1
dh -= 1
dw -= 1
rows,cols = h,w

OK = "."
NG = "#"

ss = np.array([[c=="#" for c in input()] for _ in range(h)])
inf = 1<<30
@njit((b1[:, :],i8,i8,i8,i8), cache=True)
def main(ss,ch,cw,dh,dw):
    start = ch*w+cw
    goal = dh*w+dw
    n = h*w
    seen = np.full(n, inf, np.int64)
    seen[start] = 0
    q = [(0, start)] # ワープ回数, 現在位置, 最後の道の位置
    # dx = [0,1,0,-1]
    # dy = [1,0,-1,0]
    dx = []
    dy = []
    vvs = []
    for i in range(-2,3):
        for j in range(-2,3):
            if not (i==j==0):
                dx.append(i)
                dy.append(j)
                if abs(i)+abs(j)>1:
                    vvs.append(1)
                else:
                    vvs.append(0)
    while q:
#         print(seen)
        pnum,pu = hpp(q)
        ux,uy = divmod(pu,w)
        # print(pnum,divmod(pu,w))
        if pu==goal:
            break
        for xx,yy,vv in zip(dx,dy,vvs):
    #         x = ux+xx
    #         y = uy+yy
            x,y = ux+xx, uy+yy
            u = x*w + y
            num = pnum+vv
            if x<0 or y<0 or x>=h or y>=w or ss[x][y]:
                continue
    #         print(x,y)
            if seen[u]>num:
                seen[u] = num
                hp(q,(num, u))
                
    val = seen[goal]
    if val==inf:
        return -1
    else:
        return val
print(main(ss,ch,cw,dh,dw))

Submission status: Accepted

Solution code:
import sys
input = sys.stdin.readline
from collections import deque

H,W=map(int,input().split())
sh,sw=map(int,input().split())
gh,gw=map(int,input().split())
MAP=[input().strip() for i in range(H)]

ANS=[[1<<30]*W for i in range(H)]

sh-=1
sw-=1
gh-=1
gw-=1

ANS[sh][sw]=0

Q=deque([(sh,sw)])

while Q:
    x,y=Q.popleft()

    for i in range(x-2,x+3):
        if 0<=i<H:           
            for j in range(y-2,y+3):
                if 0<=j<W:                
                    if MAP[i][j]=="." and abs(i-x)+abs(j-y)==1 and ANS[i][j]>ANS[x][y]:
                        ANS[i][j]=ANS[x][y]
                        Q.appendleft((i,j))
                    elif MAP[i][j]=="." and abs(i-x)+abs(j-y)>1 and ANS[i][j]>ANS[x][y]+1:
                        ANS[i][j]=ANS[x][y]+1
                        Q.append((i,j))

if ANS[gh][gw]==1<<30:
    print(-1)
else:
    print(ANS[gh][gw])

Submission status: Accepted

Solution code:
from collections import deque

H, W = map(int, input().split())
ch, cw = map(lambda x: int(x)-1, input().split())
dh, dw = map(lambda x: int(x)-1, input().split())
S = [list(input()) for _ in range(H)]
dist = [[-1] * W for _ in range(H)]

q = deque()
q.append((0, ch, cw))
while q:
    c, h, w = q.popleft()
    if dist[h][w] >= 0:
        continue
    dist[h][w] = c
    for hh in range(-2, 3):
        for ww in range(-2, 3):
            if 0 <= h+hh < H and 0 <= w+ww < W and S[h+hh][w+ww] == "." and dist[h+hh][w+ww] < 0:
                if (hh, ww) in ((0,1), (1,0), (-1,0), (0,-1)):
                    q.appendleft((c, h+hh, w+ww)) # 徒歩は前に追加
                else:
                    q.append((c+1, h+hh, w+ww)) # ワープは後ろに追加

print(dist[dh][dw])

Submission status: Accepted

Solution code:
import sys
from collections import deque
H, W = map(int, input().split())
c = [int(i) + 1 for i in input().split()]
d = [int(i) + 1 for i in input().split()]

s = []
s.append('#'*(W+4))
s.append('#'*(W+4))
for i in range(H):
    a = input()
    s.append('##' + a + '##')
s.append('#'*(W+4))
s.append('#'*(W+4))

q = deque([]) # 探索開始点
qq = deque([])
q.append((c[0], c[1], 0))
visited = [[False for __ in range(W+4)] for _ in range(H+4)]

while q:
    xx, yy, kaisuu = q.popleft()
    if visited[xx][yy] == True:
        continue
    qq.append((xx, yy))
    ls = deque()
    while qq:
        x, y = qq.pop()
        visited[x][y] = True
        ls.append((x, y, kaisuu))
        if x == d[0] and y == d[1]:
            print(kaisuu)
            sys.exit()
        if s[x+1][y] == '.' and visited[x+1][y] == False:
            qq.append((x+1, y))
        if s[x-1][y] == '.' and visited[x-1][y] == False:
            qq.append((x-1, y))
        if s[x][y+1] == '.' and visited[x][y+1] == False:
            qq.append((x, y+1))
        if s[x][y-1] == '.' and visited[x][y-1] == False:
            qq.append((x, y-1))
    for u in ls:
        a, b, e = u
        for i in range(-2, 3):
            for j in range(-2, 3):
                if i == 0 and j == 0:
                    continue
                if abs(i) == 1 and abs(j) == 0:
                    continue
                if abs(j) == 1 and abs(i) == 0:
                    continue
                if s[a+i][b+j] == '.' and visited[a+i][b+j] == False:
                    q.append((a+i, b+j, e+1))
print(-1)

Submission status: Accepted

Solution code:
max2 = lambda x,y: x if x > y else y
min2 = lambda x,y: x if x < y else y

import sys
from itertools import count
read = sys.stdin.buffer.read
readline = sys.stdin.buffer.readline


MOVES = [
    ((1, 0), [(2,-1),(2,0),(2,1),(2,2),(1,1)]),
    ((-1, 0),[(-2,-1),(-2,0),(-2,1),(-2,-2),(-1,-1)]),
    ((0, 1), [(1,2),(0,2),(-1,2),(-2,2),(-1,1)]),
    ((0, -1), [(1,-2),(0,-2),(-1,-2),(2,-2),(1,-1)]),
    ]

CONVERTED_MOVES = None

def solve(dist, start, goal):
    q = [start]
    cnt = 0
    while q:
        nq = []
        while q:
            x = q.pop()
            if x == goal:
                return cnt
            if dist[x] < cnt:
                continue
            for d,l in CONVERTED_MOVES:
                nx = x+d
                if dist[nx] > cnt:
                    dist[nx] = cnt
                    q.append(nx)
                if dist[nx] < 0:
                    for t in l:
                        p = x+t
                        if dist[p] > cnt+1:
                            dist[p] = cnt+1
                            nq.append(p)
        q = nq
        cnt += 1

    return -1




if __name__ == '__main__':
    H,W = map(int,readline().split())
    start = tuple(map(lambda i:int(i)+1,readline().split()))
    goal = tuple(map(lambda i:int(i)+1,readline().split()))

    H += 4
    W += 4

    dist = [-1]*(W*H)

    start = start[0]*W+start[1]
    goal = goal[0]*W+goal[1]

    for t,s in zip(count(2*W,W),read().split()):
        for i,c in zip(count(t+2),s.decode()):
            if c == '.':
                dist[i] = 10**7

    convert = lambda x,y: x*W+y
    CONVERTED_MOVES = []
    for d,l in MOVES:
        d = convert(*d)
        l = [convert(*d) for d in l]
        CONVERTED_MOVES.append((d,l))

    # print(CONVERTED_MOVES)

    print(solve(dist,start,goal))

Submission status: Accepted

Solution code:
from collections import deque

h, w = (int(x) for x in input().split())
ch, cw = (int(x) - 1 for x in input().split())
dh, dw = (int(x) - 1 for x in input().split())
s = [list(input()) for _ in range(h)]
d = [[-1] * w for _ in range(h)]
d[ch][cw] = 0
walk = [[0, 1], [0, -1], [1, 0], [-1, 0]]
warp = [[2, 2], [2, 1], [2, 0], [2, -1], [2, -2], [1, 2], [1, 1], [1, -1], [1, -2], [0, 2], [0, -2], [-1, 2], [-1, 1],
     [-1, -1], [-1, -2], [-2, 2], [-2, 1], [-2, 0], [-2, -1], [-2, -2]]

que = deque([[0, ch, cw]])
while que:
    count, y, x = que.popleft()
    if d[y][x] < count:
        continue
    for NY, NX in walk:
        if 0 <= y + NY < h and 0 <= x + NX < w and s[y + NY][x + NX] != '#':
            if d[y + NY][x + NX] == -1 or d[y + NY][x + NX] > count:
                d[y + NY][x + NX] = count
                que.appendleft([count, y + NY, x + NX])
    for NY, NX in warp:
        if 0 <= y + NY < h and 0 <= x + NX < w and s[y + NY][x + NX] != '#':
            if d[y + NY][x + NX] == -1 or d[y + NY][x + NX] > count + 1:
                d[y + NY][x + NX] = count + 1
                que.append([count + 1, y + NY, x + NX])

print(d[dh][dw])

Submission status: Accepted

Solution code:
import sys
input = sys.stdin.readline
from collections import deque

H,W=map(int,input().split())
sh,sw=map(int,input().split())
gh,gw=map(int,input().split())
MAP=[input().strip() for i in range(H)]

ANS=[[1<<30]*W for i in range(H)]

sh-=1
sw-=1
gh-=1
gw-=1

ANS[sh][sw]=0

Q=deque([(sh,sw)])

while Q:
    x,y=Q.popleft()

    for i,j in [(x-2,y-2),(x-2,y-1),(x-2,y),(x-2,y+1),(x-2,y+2),(x-1,y-2),(x-1,y-1),(x-1,y),(x-1,y+1),(x-1,y+2),(x,y-2),(x,y-1),(x,y+1),(x,y+2),(x+1,y-2),(x+1,y-1),(x+1,y),(x+1,y+1),(x+1,y+2),(x+2,y-2),(x+2,y-1),(x+2,y),(x+2,y+1),(x+2,y+2)]:
        if 0<=i<H and 0<=j<W:
            if MAP[i][j]=="." and abs(i-x)+abs(j-y)==1 and ANS[i][j]>ANS[x][y]:
                ANS[i][j]=ANS[x][y]
                Q.appendleft((i,j))
            elif MAP[i][j]=="." and abs(i-x)+abs(j-y)>1 and ANS[i][j]>ANS[x][y]+1:
                ANS[i][j]=ANS[x][y]+1
                Q.append((i,j))

if ANS[gh][gw]==1<<30:
    print(-1)
else:
    print(ANS[gh][gw])

Submission status: Accepted

Solution code:
from collections import deque

H, W = [int(_) for _ in input().split()]
C = [int(_) - 1 for _ in input().split()]
D = [int(_) - 1 for _ in input().split()]

S = [input() for _ in range(H)]
V = [[-1 for w in range(W)] for h in range(H)]

V[C[0]][C[1]] = 0

pool = deque()
pool.append(tuple([0, C[0], C[1]]))
while(pool):
    c, y, x = pool.popleft()
    if c != V[y][x]:
        continue
    for dx in [-2, -1, 0, 1, 2]:
        for dy in [-2, -1, 0, 1, 2]:
            if y + dy < 0 or H <= y + dy:
                continue
            if x + dx < 0 or W <= x + dx:
                continue
            if S[y+dy][x+dx] == "#":
                continue
            if (dx, dy) in [(-1,0),(1,0),(0,-1),(0,1)]:
                if V[y+dy][x+dx] == -1 or V[y+dy][x+dx] > V[y][x]:
                    V[y+dy][x+dx] = V[y][x]
                    pool.appendleft((c, y+dy, x+dx))
            elif V[y+dy][x+dx] == -1 or V[y+dy][x+dx] > V[y][x] + 1:
                V[y+dy][x+dx] = V[y][x] + 1
                pool.append((c+1, y+dy, x+dx))
print(V[D[0]][D[1]])

Submission status: Accepted

Solution code:
from collections import defaultdict
from collections import deque
from collections import Counter
import math

def readInt():
	return int(input())
def readInts():
	return list(map(int, input().split()))
def readChar():
	return input()
def readChars():
	return input().split()

def p(arr):
	print("_______________________")
	for i in arr:
		for j in i:
			print(j,end=" ")
		print()

h,w = readInts()
ch,cw = readInts()
dh,dw = readInts()
s = [["#" for i in range(w+2)]]+[["#"]+ list(input())+["#"] for i in range(h)]+[["#" for i in range(w+2)]]

q = deque()
visited = [[-1]*(w+2) for i in range(h+2)]
count = (w+2)*(h+2)
for i in range(h+2):
	for j in range(w+2):
		if s[i][j]=="#":
			visited[i][j] = float("inf")
			count -= 1

from pprint import pprint
visited[ch][cw] = 0

q = {(ch,cw)}
set_list = set()
cost = 0
while count:
	while len(q) !=0:
		x,y = q.pop()
		set_list.add((x,y))
		visited[x][y] = cost
		count-=1
		if s[x-1][y]=="." and visited[x-1][y]==-1:
			q.add((x-1,y))
		if s[x][y-1]=="." and visited[x][y-1]==-1:
			q.add((x,y-1))
		if s[x+1][y]=="." and visited[x+1][y]==-1:
			q.add((x+1,y))
		if s[x][y+1]=="." and visited[x][y+1]==-1:
			q.add((x,y+1))

	if len(set_list)==0:
		break

	cost+=1
	while len(set_list) != 0:
		x,y = set_list.pop()
		for dx in range(-2,3):
			for dy in range(-2,3):
				x2 = x+dx
				y2 = y+dy
				if visited[min(x2,h+1)][min(y2,w+1)]!=-1: continue
				q.add((x2,y2))

print(visited[dh][dw])

Submission status: Accepted

Solution code:
from collections import deque

h, w = map(int, input().split())
Ch, Cw = map(int, input().split())
Dh, Dw = map(int, input().split())
s = [list(input()) for _ in range(h)]

Ch, Cw = Ch - 1, Cw - 1
Dh, Dw = Dh - 1, Dw - 1
d = [[-1] * w for _ in range(h)]
d[Ch][Cw] = 0
walk = [[0, 1], [0, -1], [1, 0], [-1, 0]]
warp = [[2, 2], [2, 1], [2, 0], [2, -1], [2, -2], [1, 2], [1, 1], [1, -1], [1, -2], [0, 2], [0, -2], [-1, 2], [-1, 1],
        [-1, -1], [-1, -2], [-2, 2], [-2, 1], [-2, 0], [-2, -1], [-2, -2]]

que = deque([[0, Ch, Cw]])
while que:
    count, y, x = que.popleft()
    if d[y][x] < count:
        continue
    for NY, NX in walk:
        if 0 <= y + NY < h and 0 <= x + NX < w and s[y + NY][x + NX] != '#':
            if d[y + NY][x + NX] == -1 or d[y + NY][x + NX] > count:
                d[y + NY][x + NX] = count
                que.appendleft([count, y + NY, x + NX])
    for NY, NX in warp:
        if 0 <= y + NY < h and 0 <= x + NX < w and s[y + NY][x + NX] != '#':
            if d[y + NY][x + NX] == -1 or d[y + NY][x + NX] > count + 1:
                d[y + NY][x + NX] = count + 1
                que.append([count + 1, y + NY, x + NX])

print(d[Dh][Dw])

Submission status: Accepted

Solution code:
H,W = map(int,input().split())
Ch,Cw = map(int,input().split())
Dh,Dw = map(int,input().split())
S = [list(input()) for i in range(H)]
 
res_S = [[-1]*W for i in range(H)]
dx = [1,-1,0,0]
ddx = [-2,-1,0,1,2,-2,-1,1,2,-2,2,-2,-1,1,2,-2,-1,0,1,2]
dy = [0,0,1,-1]
ddy = [-2,-2,-2,-2,-2,-1,-1,-1,-1,0,0,1,1,1,1,2,2,2,2,2]
count = 0
 
que = [(Ch,Cw)]
que_warp =[(Ch,Cw)]
res_S[Ch-1][Cw-1] = 0
 
while (que or que_warp):
    l = len(que)
    while (que):
        if l > 0:
            que_warp.append(que[0])
            l -= 1
        for i in range(4):
            nx = int(que[0][0]+dx[i])
            ny = int(que[0][1]+dy[i])
            if (1<=nx<=H) and (1<=ny<=W):
                if res_S[nx-1][ny-1]<0 and S[nx-1][ny-1]=='.':
                    res_S[nx-1][ny-1]=count
                    que.append((nx,ny))
                    que_warp.append((nx,ny))
        que.pop(0)
 
    count += 1
 
    while(que_warp):
        for i in range(len(ddx)):
            nx = int(que_warp[0][0] + ddx[i])
            ny = int(que_warp[0][1] + ddy[i])
            if (1 <= nx <= H) and (1 <= ny <= W):
                if res_S[nx-1][ny-1]<0 and S[nx-1][ny-1]=='.':
                    res_S[nx-1][ny-1] = count
                    que.append((nx, ny))
        que_warp.pop(0)
 
print (res_S[Dh-1][Dw-1])

Submission status: Accepted

Solution code:
import collections

h, w = map(int, input().split(" "))
sr, sc = map(int, input().split(" "))
er, ec = map(int, input().split(" "))

board=[['' for i in range(w)] for j in range(h)]
for i in range(h):
    s=input()
    for j in range(w):
        board[i][j]= s[j]
rs,cs=collections.deque([sr-1]),collections.deque([sc-1])
magic=[[1e6 for i in range(w)] for j in range(h)]
dr=[-1,1,0,0]
dc=[0,0,-1,1]
magic[sr-1][sc-1]=0
while len(rs)>0:
    r,c=rs.popleft(),cs.popleft()
    for i in range(4):
        nr,nc= r+dr[i],c+dc[i]
        if nr < 0 or nr >= h or nc < 0 or nc >= w or board[nr][nc] == '#':
            continue
        if magic[nr][nc]>magic[r][c]:
            magic[nr][nc]= magic[r][c]
            rs.appendleft(nr)
            cs.appendleft(nc)
    #wizard
    for nr in range(r-2,r+3):
        for nc in range(c-2,c+3):
            if nr < 0 or nr >= h or nc < 0 or nc >= w or board[nr][nc] == '#':
                continue
            if magic[nr][nc] > magic[r][c]+1:
                    magic[nr][nc] = magic[r][c]+1
                    rs.append(nr)
                    cs.append(nc)
print(magic[er-1][ec-1] if magic[er-1][ec-1]<1e6 else -1)

Submission status: Accepted

Solution code:
from collections import deque
lrud = [[0, -1], [0, 1], [-1, 0], [1, 0]]
magic = [[i, j] for i in range(-2, 3) for j in range(-2, 3)]
H, W = map(int, input().split())
Ch, Cw = map(int, input().split())
Ch, Cw = Ch-1, Cw-1
Dh, Dw = map(int, input().split())
Dh, Dw = Dh-1, Dw-1
S = [list(input()) for i in range(H)]
is_visited = [[-1 for j in range(W)]for i in range(H)]

d = deque()
d.appendleft((0, (Ch, Cw)))
while d:
    cost, (x, y) = d.popleft()
    if is_visited[x][y] != -1:
        continue
    is_visited[x][y] = cost
    for dx, dy in lrud:
        nx, ny = x+dx, y+dy
        if 0 <= nx < H and 0 <= ny < W and is_visited[nx][ny] == -1 and S[nx][ny] == '.':
            d.appendleft((cost, (nx,ny)))
    for dx, dy in magic:
        nx, ny = x+dx, y+dy
        if 0 <= nx < H and 0 <= ny < W and is_visited[nx][ny] == -1 and S[nx][ny] == '.':
            d.append((cost+1, (nx,ny)))

# print(is_visited)
print(is_visited[Dh][Dw])

Submission status: Accepted

Solution code:
#辺の重み(変化量)が0である場合は01DFSって特別なやつ
#0の場合はそこでBFSできる
import sys
from collections import deque
sys.setrecursionlimit(10**7)
input=sys.stdin.readline
h,w=map(int,input().split())
c=[int(i)-1 for i in input().split()]
d=[int(i)-1 for i in input().split()]
s=[input() for i in range(h)]
inf=100000000
dp=[[-1 if s[i][j]=="#" else inf for j in range(w)] for i in range(h)]
dp[c[0]][c[1]]=0
now=deque([[c[0],c[1]]])
def bfs():
    global h,w,s,dp,now
    while len(now):
        i,j=now.popleft()
        if i>0:
            if dp[i-1][j]!=-1:
                if dp[i-1][j]>dp[i][j]:
                    dp[i-1][j]=dp[i][j]
                    now.appendleft([i-1,j])
        if j>0:
            if dp[i][j-1]!=-1:
                if dp[i][j-1]>dp[i][j]:
                    dp[i][j-1]=dp[i][j]
                    now.appendleft([i,j-1])
        if i<h-1:
            if dp[i+1][j]!=-1:
                if dp[i+1][j]>dp[i][j]:
                    dp[i+1][j]=dp[i][j]
                    now.appendleft([i+1,j])
        if j<w-1:
            if dp[i][j+1]!=-1:
                if dp[i][j+1]>dp[i][j]:
                    dp[i][j+1]=dp[i][j]
                    now.appendleft([i,j+1])
        for k in range(-2,3):
            for l in range(-2,3):
                if 0<=i+k<h and 0<=j+l<w:
                    if dp[i+k][j+l]!=-1:
                        if dp[i+k][j+l]>dp[i][j]+1:
                            dp[i+k][j+l]=dp[i][j]+1
                            now.append([i+k,j+l])
bfs()
print(dp[d[0]][d[1]] if dp[d[0]][d[1]]!=inf else -1)

Submission status: Accepted

Solution code:
from collections import deque
H,W=map(int,input().split())
c=list(map(int,input().split()))
d=list(map(int,input().split()))
s=[list(input()) for _ in range(H)]
INF=10000000
dp=[[INF for _ in range(W)] for _ in range(H)]

def walk_bfs(y,x,v):
  # 歩ける範囲で歩き潰す
  dp[y][x] = v
  path = deque()
  path.append([y,x])
  ret = deque()
  while path:
    y,x = path.popleft()
    ret.append([y,x])
    for i,j in ((0,1),(0,-1),(1,0),(-1,0)):
      if not (0 <= y+i < H and 0 <= x+j < W):
        continue
      if s[y+i][x+j] == '#':
        dp[y+i][x+j] = -1
      elif dp[y+i][x+j] == INF:
        dp[y+i][x+j] = v
        path.append([y+i,x+j])
  return ret

def warp_bfs():
  # ワープ回数でbfsとる
  deq = walk_bfs(c[0]-1,c[1]-1,0)
  while deq:
    y,x = deq.popleft()
    for yi in range(max(0,y-2),min(H,y+3)):
      for xi in range(max(0,x-2),min(W,x+3)):
        if s[yi][xi]=='#':
          dp[yi][xi] = -1
          continue
        if dp[yi][xi]==INF:
          deq.extend(walk_bfs(yi,xi,dp[y][x]+1))

warp_bfs()
ans = dp[d[0]-1][d[1]-1]
if 0<= ans < INF:
  print(ans)
else:
  print(-1)
#print(dp)

Submission status: Accepted

Solution code:

from collections import deque


H, W = [int(x) for x in input().split()]
Ch, Cw = [int(x) - 1 for x in input().split()]
Dh, Dw = [int(x) - 1 for x in input().split()]

warp_list = [(-2, -2), (-2, -1), (-2, 0), (-2, 1), (-2, 2),
             (-1, -2), (-1, -1), (-1, 1), (-1, 2),
             (0, -2), (0, 2),
             (1, -2), (1, -1), (1, 1), (1, 2),
             (2, -2), (2, -1), (2, 0), (2, 1), (2, 2)]

maze = []
warp_count = []
for _ in range(H):
    line = list([x for x in input()])
    maze.append(line)
    warp_count.append([-1] * W)

queue = deque()
warp_queue = deque()

queue.appendleft((Ch, Cw, 0))
warp_count[Ch][Cw] = 0

answer = -1
warp_set = set()
while queue:
    def maze_check(h, w, use_magic):
        if h < 0 or H <= h:
            return False
        if w < 0 or W <= w:
            return False
        if warp_count[h][w] == -1:
            return True
        if warp_count[h][w] <= use_magic:
            return False

    def is_wall(h, w):
        if maze[h][w] == '#':
            return True
        return False

    now_h, now_w, use_magic = queue.pop()

    if now_h == Dh and now_w == Dw:
        if answer == -1:
            answer = use_magic

        elif answer > use_magic:
            answer = use_magic

        continue

    # 上下左右に移動
    for y, x in [(1, 0), (-1, 0), (0, 1), (0, -1)]:
        if maze_check(now_h + y, now_w + x, use_magic):

            # 上下左右、いずれかに壁がある場合にはワープ先に行く可能性がある
            if is_wall(now_h + y, now_w + x):
                if not (now_h, now_w) in warp_set:
                    warp_queue.appendleft((now_h, now_w, use_magic))
                    warp_set.add((now_h, now_w))
            else:
                queue.appendleft((now_h + y, now_w + x, use_magic))
                warp_count[now_h + y][now_w + x] = use_magic

    if not queue:
        while warp_queue:
            now_h, now_w, use_magic = warp_queue.pop()

            for y, x in warp_list:
                warp_h = now_h + y
                warp_w = now_w + x

                if maze_check(warp_h, warp_w, use_magic+1):
                    if not is_wall(warp_h, warp_w):
                        queue.append((warp_h, warp_w, use_magic+1))
                        warp_count[warp_h][warp_w] = use_magic + 1
        warp_set = set()

print(answer)

Submission status: Accepted

Solution code:
from collections import deque

H, W = map(int, input().split())
Si, Sj = map(int, input().split())
Gi, Gj = map(int, input().split())

S = ["#" * (W + 2)] + ["#" + input() + "#" for _ in range(H)] + ["#" * (W + 2)]

INF = float("inf")
D = [[INF] * (W + 2) for _ in range(H + 2)]
D[Si][Sj] = 0
Q = deque([(0, Si, Sj)])
while Q:
    c, i, j = Q.popleft()
    if (i, j) == (Gi, Gj):
        print(D[i][j])
        quit()

    for ni, nj in [(i + 1, j), (i - 1, j), (i, j + 1), (i, j - 1)]:
        if 1 <= ni <= H and 1 <= nj <= W and D[ni][nj] > c and S[ni][nj] == ".":
            D[ni][nj] = c
            Q.appendleft((c, ni, nj))

    for di in range(-2, 3):
        for dj in range(-2, 3):
            ni, nj = i + di, j + dj
            if 1 <= ni <= H and 1 <= nj <= W and (di, dj) not in [(1, 0), (0, 1), (-1, 0), (0, -1), (0, 0)] and D[ni][nj] > c + 1 and S[ni][nj] == ".":
                D[ni][nj] = c + 1
                Q.append((c + 1, ni, nj))

print(-1)

Submission status: Accepted

Solution code:

 
dx = [-1,0,1,0]
dy = [0,-1,0,1]
 
def bfs(ch,cw):
    q = [[] for _ in range(1000000)]
    
    S[ch][cw] = 0
    q[S[ch][cw]].append([ch,cw])
    
    counter = 0
    
    while True:
        if not q[counter]:
          counter += 1
          if not q[counter]:
              break
        p = q[counter].pop()
        
        if p[0]==dh and p[1]==dw:
            break
        
        for i in range(4):
            next_p = [p[0]+dx[i],p[1]+dy[i]]
            if next_p[0]<0 or next_p[1]<0 or next_p[0]>=h or next_p[1]>=w:
                continue
            if S[next_p[0]][next_p[1]] > S[p[0]][p[1]]:
                S[next_p[0]][next_p[1]] = S[p[0]][p[1]]
                q[counter].append(next_p)
                
                
        for i in range(-2,3):
            for j in range(-2,3):
                if (i == 0 and j == 0) or (i==-1 and j==0)or(i==1 and j==0)or(i==0 and j==-1)or (i==0 and j==1):
                    continue
                next_p = [p[0]+i,p[1]+j]
                if next_p[0]<0 or next_p[1]<0 or next_p[0]>=h or next_p[1]>=w:
                    continue
                if S[next_p[0]][next_p[1]] > S[p[0]][p[1]]+1:
                    S[next_p[0]][next_p[1]] = S[p[0]][p[1]]+1
                    q[counter+1].append(next_p)
                    
            
    return 
        
h,w = map(int,input().split())
ch,cw = map(int,input().split())
ch -= 1
cw -= 1
dh,dw = map(int,input().split())
dh -= 1
dw -= 1
S = [list(input()) for _ in range(h)]
 
for i in range(h):
    for j in range(w):
        if S[i][j] == '.':
            S[i][j] = float('inf')
        else:
            S[i][j] = -1
 
 
bfs(ch,cw)
if S[dh][dw] != float('inf'):
    print(S[dh][dw])
else:
    print(-1)