Problem p03682 (python)

Fixed submission:
import sys
sys.setrecursionlimit(10**6)
from heapq import heappop, heappush,heapify

icase=0
if icase==0:
    n=int(input())
    xy=[[0]*2 for i in range(n)]
    x=[0]*n
    y=[0]*n
    for i in range(n):
#        xy[i]=list(map(int,input().split()))
        x[i],y[i]=map(int,input().split())
elif icase==1:    
    n=3
#    xy=[[1, 5], [3, 9], [7, 8]]
    x=[1, 3, 7]
    y=[5, 9, 8]
elif icase==2:    
    n=6
#    xy=[[8, 3], [4, 9], [12, 19], [18, 1], [13, 5], [7, 6]]
    x=[8, 4, 12,18,13,7]
    y=[3, 9, 19, 1, 5, 6]

xi=[[0]*2 for i in range(n)]
yi=[[0]*2 for i in range(n)]
for i in range(n):
    xi[i]=[x[i],i]
    yi[i]=[y[i],i]
    
xi.sort()
x=xi
y=yi.sort()
y=yi

pair_lst = [i for i in range(n)]
que=[]
for i in range(n-1):
    wi=x[i+1][0]-x[i][0]
    heappush(que,(wi,x[i][1],x[i+1][1]))
    wi=y[i+1][0]-y[i][0]
    heappush(que,(wi,y[i][1],y[i+1][1]))

def find(x):
    if x == pair_lst[x]:
        return x
    else:
        tmp = find(pair_lst[x])
        pair_lst[x] = tmp
        return tmp

icnt=0
length_sum = 0
while que:
    w, s, t = heappop(que)
#    print(w,s,t)
    root_s = find(s)
    root_t = find(t)
    if root_s != root_t:
        pair_lst[root_s] = root_t
        length_sum += w
        icnt+=1
#        print(icnt)

print(length_sum)

Buggy submission (verdict: Runtime Error):
import sys
sys.setrecursionlimit(10**6)
from heapq import heappop, heappush,heapify

icase=0
if icase==0:
    n=int(input())
    xy=[[0]*2 for i in range(n)]
    for i in range(n):
        xy[i]=list(map(int,input().split()))
elif icase==1:    
    n=3
    xy=[[1, 5], [3, 9], [7, 8]]
elif icase==2:    
    n=6
    xy=[[8, 3], [4, 9], [12, 19], [18, 1], [13, 5], [7, 6]]

xy = list(map(list, set(map(tuple, xy))))
#xy.sort()

pair_lst = [i for i in range(n)]
que=[]
for i in range(n-1):
    for j in range(i+1,n):
        wi=min(abs(xy[i][0]-xy[j][0]),abs(xy[i][1]-xy[j][1]))
#        que.append((wi,i,j))
        heappush(que,(wi,i,j))

def find(x):
    if x == pair_lst[x]:
        return x
    else:
        tmp = find(pair_lst[x])
        pair_lst[x] = tmp
        return tmp

icnt=0
length_sum = 0
while que:
    w, s, t = heappop(que)
    root_s = find(s)
    root_t = find(t)
    if root_s != root_t:
        pair_lst[root_s] = root_t
        length_sum += w
        icnt+=1
#        print(icnt)
        if icnt==n-1:
            break

print(length_sum)

Buggy submission (verdict: Runtime Error):
import sys
sys.setrecursionlimit(10**6)
from heapq import heappop, heappush

icase=0
if icase==0:
    n=int(input())
    xy=[[0]*2 for i in range(n)]
    for i in range(n):
        xy[i]=list(map(int,input().split()))
elif icase==1:    
    n=3
    xy=[[1, 5], [3, 9], [7, 8]]
elif icase==2:    
    n=6
    xy=[[8, 3], [4, 9], [12, 19], [18, 1], [13, 5], [7, 6]]

xy = list(map(list, set(map(tuple, xy))))
xy.sort()
xy=xy[:n]

pair_lst = [i for i in range(n)]
que=[]
for i in range(n-1):
    for j in range(i+1,n):
        wi=min(abs(xy[i][0]-xy[j][0]),abs(xy[i][1]-xy[j][1]))
        heappush(que,(wi,i,j))

def find(x):
    if x == pair_lst[x]:
        return x
    else:
        tmp = find(pair_lst[x])
        pair_lst[x] = tmp
        return tmp

length_sum = 0
while que:
    w, s, t = heappop(que)
    root_s = find(s)
    root_t = find(t)
    if root_s != root_t:
        pair_lst[root_s] = root_t
        length_sum += w

print(length_sum)

Buggy submission (verdict: Runtime Error):
import sys
sys.setrecursionlimit(10**6)
from heapq import heappop, heappush

icase=0
if icase==0:
    n=int(input())
    xy=[[0]*2 for i in range(n)]
    for i in range(n):
        xy[i]=list(map(int,input().split()))
elif icase==1:    
    n=3
    xy=[[1, 5], [3, 9], [7, 8]]
elif icase==2:    
    n=6
    xy=[[8, 3], [4, 9], [12, 19], [18, 1], [13, 5], [7, 6]]

xy = list(map(list, set(map(tuple, xy))))
xy.sort()
xy=xy[:n*2]

pair_lst = [i for i in range(n)]
que=[]
for i in range(n-1):
    for j in range(i+1,n):
        wi=min(abs(xy[i][0]-xy[j][0]),abs(xy[i][1]-xy[j][1]))
        heappush(que,(wi,i,j))

def find(x):
    if x == pair_lst[x]:
        return x
    else:
        tmp = find(pair_lst[x])
        pair_lst[x] = tmp
        return tmp

length_sum = 0
while que:
    w, s, t = heappop(que)
    root_s = find(s)
    root_t = find(t)
    if root_s != root_t:
        pair_lst[root_s] = root_t
        length_sum += w

print(length_sum)