Problem: There is a grass field that stretches infinitely.  In this field, there is a negligibly small cow. Let (x, y) denote the point that is x\ \mathrm{cm} south and y\ \mathrm{cm} east of the point where the cow stands now. The cow itself is standing at (0, 0).  There are also N north-south lines and M east-west lines drawn on the field. The i-th north-south line is the segment connecting the points (A_i, C_i) and (B_i, C_i), and the j-th east-west line is the segment connecting the points (D_j, E_j) and (D_j, F_j).  What is the area of the region the cow can reach when it can move around as long as it does not cross the segments (including the endpoints)? If this area is infinite, print `INF` instead.

Submission attempts (in order):
import numpy as np
from bisect import *
n, m = map(int, input().split())
a, b, c = zip(*(map(int, input().split()) for _ in range(n)))
d, e, f = zip(*(map(int, input().split()) for _ in range(m)))
x = sorted(set(c + e + f))
y = sorted(set(a + b + d))
h = len(y)-1
w = len(x)-1
def tx(i):
    return bisect(x, i)-1
def ty(i):
    return bisect(y, i)-1
u = np.ones((h+1, w))
for d, e, f in zip(d, e, f):
    d, e, f = ty(d), tx(e), tx(f)
    u[d, e:f] = false
l = np.ones((h, w+1))
for a ,b, c in zip(a, b, c):
    a, b, c = ty(a), ty(b), tx(c)
    l[a:b, c] = false
s = np.outer(np.diff(y), np.diff(x)) 
i = bisect(y, 0)-1
j = bisect(x, 0)-1
s = [(i,j)]
v = set()
r = 0
while s:
    i, j = s.pop()
    if (i,j) in v:
        continue
    v.add((i,j))
    if not (0<=i<h and 0<=j<w):
        print('inf')
        break
    r += s[i][j]
    if u[i][j]:
        s.append((i-1,j))
    if u[i+1][j]:
        s.append((i+1,j))
    if l[i][j]:
        s.append((i,j-1))
    if l[i][j+1]:
        s.append((i,j+1))
else:
    print(r)

import numpy as np
from bisect import *
n, m = map(int, input().split())
A, B, C = zip(*(map(int, input().split()) for _ in range(n)))
D, E, F = zip(*(map(int, input().split()) for _ in range(m)))
X = sorted(set(C + E + F))
Y = sorted(set(A + B + D))
H = len(Y)-1
W = len(X)-1
def TX(i):
    return bisect(X, i)-1
def TY(i):
    return bisect(Y, i)-1
U = np.ones((H+1, W))
for d, e, f in zip(D, E, F):
    d, e, f = TY(d), TX(e), TX(f)
    U[d, e:f] = False
L = np.ones((H, W+1))
for a ,b, c in zip(A, B, C):
    a, b, c = TY(a), TY(b), TX(c)
    L[a:b, c] = False
S = np.outer(np.diff(Y), np.diff(X)) 
i = bisect(Y, 0)-1
j = bisect(X, 0)-1
s = [(i,j)]
exit()
v = set()
r = 0
while s:
    i, j = s.pop()
    if (i,j) in v:
        continue
    v.add((i,j))
    if not (0<=i<H and 0<=j<W):
        print('INF')
        break
    r += S[i][j]
    if U[i][j]:
        s.append((i-1,j))
    if U[i+1][j]:
        s.append((i+1,j))
    if L[i][j]:
        s.append((i,j-1))
    if L[i][j+1]:
        s.append((i,j+1))
else:
    print(r)


import numpy as np
from numba import njit
from bisect import *
n, m = map(int, input().split())
A, B, C = zip(*(map(int, input().split()) for _ in range(n)))
D, E, F = zip(*(map(int, input().split()) for _ in range(m)))
X = sorted(set(C + E + F))
Y = sorted(set(A + B + D))
H = len(Y)-1
W = len(X)-1
def TX(i):
    return bisect(X, i)-1
def TY(i):
    return bisect(Y, i)-1
U = np.ones((H+1, W))
for d, e, f in zip(D, E, F):
    d, e, f = TY(d), TX(e), TX(f)
    U[d, e:f] = False
L = np.ones((H, W+1))
for a ,b, c in zip(A, B, C):
    a, b, c = TY(a), TY(b), TX(c)
    L[a:b, c] = False
S = np.outer(np.diff(Y), np.diff(X)) 
@njit
def f(i,j):
    s = [(i,j)]
    v = set()
    r = 0
    while s:
        i, j = s.pop()
        if (i,j) in v:
            continue
        v.add((i,j))
        if not (0<=i<H and 0<=j<W):
            print('INF')
            break
        r += S[i][j]
        if U[i][j]:
            s.append((i-1,j))
        if U[i+1][j]:
            s.append((i+1,j))
        if L[i][j]:
            s.append((i,j-1))
        if L[i][j+1]:
            s.append((i,j+1))
    else:
        print(r)
f()

import numpy as np
from bisect import *
A, B, C = zip(*(map(int, input().split()) for _ in range(n)))
D, E, F = zip(*(map(int, input().split()) for _ in range(m)))
X = sorted(set(C + E + F))
Y = sorted(set(A + B + D))
H = len(Y)-1
W = len(X)-1
def TX(i):
    return bisect(X, i)-1
def TY(i):
    return bisect(Y, i)-1
U = np.ones((H+1, W))
for d, e, f in zip(D, E, F):
    d, e, f = TY(d), TX(e), TX(f)
    U[d, e:f] = False
L = np.ones((H, W+1))
for a ,b, c in zip(A, B, C):
    a, b, c = TY(a), TY(b), TX(c)
    L[a:b, c] = False
S = np.outer(np.diff(Y), np.diff(X)) 
i = bisect(Y, 0)-1
j = bisect(X, 0)-1
s = [(i,j)]
v = set()
r = 0
while s:
    i, j = s.pop()
    if (i,j) in v:
        continue
    v.add((i,j))
    if not (0<=i<H and 0<=j<W):
        print('INF')
        break
    r += S[i][j]
    if U[i][j]:
        s.append((i-1,j))
    if U[i+1][j]:
        s.append((i+1,j))
    if L[i][j]:
        s.append((i,j-1))
    if L[i][j+1]:
        s.append((i,j+1))
else:
    print(r)


import numpy as np
from numba import njit
from bisect import *
n, m = map(int, input().split())
A, B, C = zip(*(map(int, input().split()) for _ in range(n)))
D, E, F = zip(*(map(int, input().split()) for _ in range(m)))
X = sorted(set(C))
Y = sorted(set(D))
H = len(Y)-1
W = len(X)-1
def TX(i):
    return bisect(X, i)-1
def TY(i):
    return bisect(Y, i)-1
U = np.ones((H+1, W))
for d, e, f in zip(D, E, F):
    #d, e, f = TY(d), TX(e), TX(f)
    d = TY(d)
    e = bisect_left(X, e)
    f = bisect_right(X, f)-1
    U[d, e:f] = False
L = np.ones((H, W+1))
for a ,b, c in zip(A, B, C):
    #a, b, c = TY(a), TY(b), TX(c)
    c = TX(c)
    a = bisect_left(Y, a)
    b = bisect_right(Y, b)-1
    L[a:b, c] = False
S = np.outer(np.diff(Y), np.diff(X))
@njit
def dfs(i, j):
    s = [(i,j)]
    v = np.zeros((H,W))
    r = 0
    while s:
        i, j = s.pop()
        if not (0<=i<H and 0<=j<W):
            return -1
        if v[i,j]:
            continue
        v[i,j] = True
        r += S[i,j]
        if U[i,j]:
            s.append((i-1,j))
        if U[i+1,j]:
            s.append((i+1,j))
        if L[i,j]:
            s.append((i,j-1))
        if L[i,j+1]:
            s.append((i,j+1))
    return r
r = dfs(TY(0), TX(0))
print('INF' if r<0 else r)

Verdicts: Runtime Error

Wrong Answer

Runtime Error

Runtime Error

Accepted