Buggy python submission (verdict: Runtime Error):
import sys
input = lambda : sys.stdin.readline().rstrip()
sys.setrecursionlimit(max(1000, 10**9))
write = lambda x: sys.stdout.write(x+"\n")


import math
n,k = map(int, input().split())
a = list(map(int, input().split()))
a1 = [item for item in a if item>0]
a2 = [item for item in a if item<0]
n1 = sum(item>0 for item in a)
n2 = sum(item<0 for item in a)
nz = sum(item==0 for item in a)
a1.sort(reverse=True)
a2.sort()
c1 = [math.log2(item) for item in a1]
c2 = [math.log2(-item) for item in a2]
def cumsum(a):
    """l[i] = sum(a[:i]) なるlを返す
    sum(a[i:j]) == l[j+1] - l[i]
    """
    c = 0
    l = [None] * (len(a)+1)
    for i,num in enumerate(a):
        l[i] = c
        c += num
    l[-1] = c
    return l
cc1 = cumsum(c1)
cc2 = cumsum(c2)
if n1+n2<k:
    ans = 0
else:
    best = -10**12
    ind = None
    for i in range(n2//2+1):
        if 2*i>k:
            continue
        if 2*i+n1+nz<k:
            continue
        if k-2*i<=n1:
            val = cc2[2*i] + cc1[k-2*i]
            if val>best:
                ind = i
                best = val
    M = 10**9+7
    if ind is None:
        if nz>0:
            ans = 0
        else:
            # マイナスだけ
            ans = 1
            for i in range(k):
                ans *= a2[-(i+1)]
                ans %= M
    else:
        ans = 1
        for i in range(2*i):
            ans *= a2[i]
            ans %= M
        for i in range(k-2*i):
            ans *= a1[i]
            ans %= M
print(ans)

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


import math
n,k = map(int, input().split())
a = list(map(int, input().split()))
a1 = [item for item in a if item>0]
a2 = [item for item in a if item<0]
n1 = sum(item>0 for item in a)
n2 = sum(item<0 for item in a)
nz = sum(item==0 for item in a)
a1.sort(reverse=True)
a2.sort()
c1 = [math.log10(item) for item in a1]
c2 = [math.log10(-item) for item in a2]
def cumsum(a):
    """l[i] = sum(a[:i]) なるlを返す
    sum(a[i:j]) == l[j+1] - l[i]
    """
    c = 0
    l = [None] * (len(a)+1)
    for i,num in enumerate(a):
        l[i] = c
        c += num
    l[-1] = c
    return l
cc1 = cumsum(c1)
cc2 = cumsum(c2)
if n1+n2<k:
    ans = 0
else:
    best = -10**12
    ind = None
    for i in range(n2//2+1):
        # マイナスを偶数個
        if 2*i>k:
            continue
        if 2*i+n1<k:
            continue
        if k-2*i<=n1:
            val = cc2[2*i] + cc1[k-2*i]
            if val>best:
                ind = i
                best = val
    M = 10**9+7
    if ind is None:
        if nz>0:
            ans = 0
        else:
            # マイナスだけ
            ans = 1
            if k<=n2:
                for i in range(k):
                    ans *= a2[-(i+1)]
                    ans %= M
            else:
                for i in range(n2):
                    ans *= a2[i]
                    ans %= M
                for i in range(n1):
                    ans *= a1[i]
                    ans %= M
    else:
        ans = 1
        for i in range(2*ind):
            ans *= a2[i]
            ans %= M
        for i in range(k-2*ind):
            ans *= a1[i]
            ans %= M
print(ans)