Buggy python submission (verdict: Time Limit Exceeded):
N, K = map(int, input().split())
x_list = [0]*N
y_list = [0]*N
for i in range(N):
    x_list[i], y_list[i] = map(int, input().split())

x_sort_list = sorted(x_list)
y_sort_list = sorted(y_list)
ans = float("inf")

for i in range(len(x_sort_list)):
    for j in range(len(y_sort_list)):
        for k in range(i+1, len(x_sort_list)):
            for l in range(j+1, len(y_sort_list)):
                num = 0
                for m in range(N):
                    if x_sort_list[i] <= x_list[m] <= x_sort_list[k] and y_sort_list[j] <= y_list[m] <= y_sort_list[l]:
                        num += 1
                if num >= K:
                    ans = min((x_sort_list[k] - x_sort_list[i]) * (y_sort_list[l] - y_sort_list[j]), ans)

print(ans)


Fixed submission:
N, K = map(int, input().split())
x_list = [0]*N
y_list = [0]*N
for i in range(N):
    x_list[i], y_list[i] = map(int, input().split())

x_element = sorted(set(x_list))
y_element = sorted(set(y_list))
ans = float("inf")

for i in range(len(x_element)):
    for j in range(len(y_element)):
        for k in range(i+1, len(x_element)):
            for l in range(j+1, len(y_element)):
                num = 0
                for m in range(N):
                    if x_element[i] <= x_list[m] <= x_element[k] and y_element[j] <= y_list[m] <= y_element[l]:
                        num += 1
                if num >= K:
                    ans = min((x_element[k] - x_element[i]) * (y_element[l] - y_element[j]), ans)

print(ans)

Buggy python submission (verdict: Runtime Error):
n, k = map(int, input().split())
x_list = [0]*n
y_list = [0]*n
for i in range(n):
    x_list[i], y_list[i] = map(int, input().split())

x_element = set(x_list)
y_element = set(y_list)
ans = float("inf")

for i in range(len(x_element)):
    for j in range(len(y_element)):
        for k in range(i+1, len(x_element)):
            for l in range(j+1, len(y_element)):
                num = 0
                for m in range(n):
                    x_left = x_element[i]
                    x_right = x_element[k]
                    y_bottom = y_element[j]
                    y_upper = y_element[l]
                    if x_left <= x_list[m] <= x_right and y_bottom <= y_list[m] <= y_upper:
                        num += 1
                    if num >= k:
                        ans = min((x_right - x_left) * (y_upper - y_bottom), ans)

print(ans)

Fixed submission:
N, K = map(int, input().split())
x_list = [0]*N
y_list = [0]*N
for i in range(N):
    x_list[i], y_list[i] = map(int, input().split())

x_element = sorted(set(x_list))
y_element = sorted(set(y_list))
ans = float("inf")

for i in range(len(x_element)):
    for j in range(len(y_element)):
        for k in range(i+1, len(x_element)):
            for l in range(j+1, len(y_element)):
                num = 0
                for m in range(N):
                    if x_element[i] <= x_list[m] <= x_element[k] and y_element[j] <= y_list[m] <= y_element[l]:
                        num += 1
                if num >= K:
                    ans = min((x_element[k] - x_element[i]) * (y_element[l] - y_element[j]), ans)

print(ans)

Buggy python submission (verdict: Runtime Error):
n, k = map(int, input().split())
x_list = [0]*n
y_list = [0]*n
for i in range(n):
    x_list[i], y_list[i] = map(int, input().split())

x_element = set(x_list)
y_element = set(y_list)
ans = float("inf")

for i in range(len(x_element)):
    for j in range(len(y_element)):
        for k in range(i+1, len(x_element)):
            for l in range(j+1, len(y_element)):
                num = 0
                for m in range(n):
                    x_left = x_element[i]
                    x_right = x_element[k]
                    y_bottom = y_element[j]
                    y_upper = y_element[l]
                    if x_left <= x[m] <= x_right and y_bottom <= y[m] <= y_upper:
                        num += 1
                    if num >= k:
                        ans = min((x_right - x_left) * (y_upper - y_bottom), ans)

print(ans)

Fixed submission:
N, K = map(int, input().split())
x_list = [0]*N
y_list = [0]*N
for i in range(N):
    x_list[i], y_list[i] = map(int, input().split())

x_element = sorted(set(x_list))
y_element = sorted(set(y_list))
ans = float("inf")

for i in range(len(x_element)):
    for j in range(len(y_element)):
        for k in range(i+1, len(x_element)):
            for l in range(j+1, len(y_element)):
                num = 0
                for m in range(N):
                    if x_element[i] <= x_list[m] <= x_element[k] and y_element[j] <= y_list[m] <= y_element[l]:
                        num += 1
                if num >= K:
                    ans = min((x_element[k] - x_element[i]) * (y_element[l] - y_element[j]), ans)

print(ans)