Buggy python submission (verdict: Runtime Error):
import sys
def input(): return sys.stdin.readline().strip()
def mapint(): return map(int, input().split())
sys.setrecursionlimit(10**9)

N, K = mapint()
As = list(mapint())
mod = 10**9+7

pos = []
neg = []
for a in As:
    if a>=0:
        pos.append(a)
    else:
        neg.append(a)
pos.sort(reverse=True)
neg.sort(reverse=True)
ans = 1
lenp, lenn = len(pos), len(neg)
if (lenp+lenn)==K:
    for a in As:
        ans *= a
        ans %= mod
    print(ans)
elif lenn==0:
    for i in range(K):
        ans *= pos[i]
        ans %= mod
    print(ans)
elif lenp==0:
    if K%2==0:
        for i in range(K):
            ans *= neg[i]
            ans %= mod
        print(ans)
    else:
        for i in range(K-1, -1, -1):
            ans *= neg[i]
            ans %= mod
        print(ans)        
else:
    p, n = 0, 0
    while p+n+1<K:
        if p+2<lenp and n+2<lenn:
            if pos[p]*pos[p+1]>=neg[n]*neg[n+1]:
                ans *= pos[p]
                p += 1
            else:
                ans *= neg[n]*neg[n+1]
                n += 2
        elif n+2<lenn:
            ans *= neg[n]*neg[n+1]
            n += 2
        else:
            ans *= pos[p]
            p += 1
        ans %= mod
    if p+n<K:
        ans *= pos[p]
        ans %= mod
    print(ans)

Fixed submission:
import sys
def input(): return sys.stdin.readline().strip()
def mapint(): return map(int, input().split())
sys.setrecursionlimit(10**9)

def solve():
    N, K = mapint()
    As = list(mapint())
    mod = 10**9+7
    pos = []
    neg = []
    for a in As:
        if a>=0:
            pos.append(a)
        else:
            neg.append(a)

    pos.sort(reverse=True)
    neg.sort()
    lenp = len(pos)
    lenn = len(neg)
    if not pos and K%2==1:
        ans = 1
        for i, n in enumerate(neg[::-1]):
            ans *= n
            ans %= mod
            if i==K-1:
                break
        return ans
    if lenp+lenn==K and (K-lenp)%2==1:
        ans = 1
        pos.extend(neg)
        pos.sort(reverse=True)
        for i, p in enumerate(pos):
            ans *= p
            ans %= mod
            if i==K-1:
                break
        return ans
    ans = 1
    pcnt = 0
    ncnt = 0
    for i in range(K//2):
        if pcnt*2+1>=lenp:
            ans *= neg[ncnt*2]*neg[ncnt*2+1]
            ans %= mod
            ncnt += 1
        elif ncnt*2+1>=lenn:
            ans *= pos[pcnt*2]*pos[pcnt*2+1]
            ans %= mod
            pcnt += 1
        elif pos[pcnt*2]*pos[pcnt*2+1]>neg[ncnt*2]*neg[ncnt*2+1]:
            ans *= pos[pcnt*2]*pos[pcnt*2+1]
            ans %= mod
            pcnt += 1
        else:
            ans *= neg[ncnt*2]*neg[ncnt*2+1]
            ans %= mod
            ncnt += 1
    if K%2==1:
        ans *= pos[pcnt*2]
        ans %= mod
    return ans

print(solve())

Buggy python submission (verdict: Runtime Error):
import sys
def input(): return sys.stdin.readline().strip()
def mapint(): return map(int, input().split())
sys.setrecursionlimit(10**9)

N, K = mapint()
As = list(mapint())
mod = 10**9+7

pos = []
neg = []
for a in As:
    if a>=0:
        pos.append(a)
    else:
        neg.append(a)
pos.sort(reverse=True)
neg.sort(reverse=True)
ans = 1
lenp, lenn = len(pos), len(neg)
if (lenp+lenn)==K:
    for a in As:
        ans *= a
        ans %= mod
    print(ans)
elif lenn==0:
    for i in range(K):
        ans *= pos[i]
        ans %= mod
    print(ans)
elif lenp==0:
    if K%2==0:
        for i in range(K):
            ans *= neg[i]
            ans %= mod
        print(ans)
    else:
        for i in range(K-1, -1, -1):
            ans *= neg[i]
            ans %= mod
        print(ans)        
else:
    cur = 0
    p, n = 0, 0
    while p+n+1<K:
        if p+2<=lenp and n+2<=lenn:
            if pos[p]*pos[p+1]>=neg[n]*neg[n+1]:
                ans *= pos[p]
                p += 1
            else:
                ans *= neg[n]*neg[n+1]
                n += 2
        elif n+2<=lenn:
            ans *= neg[n]*neg[n+1]
            n += 2
        else:
            ans *= pos[p]
            p += 1
        ans %= mod
    if p+n<K:
        ans *= pos[p+1]
        ans %= mod
    print(ans)

Fixed submission:
import sys
def input(): return sys.stdin.readline().strip()
def mapint(): return map(int, input().split())
sys.setrecursionlimit(10**9)

def solve():
    N, K = mapint()
    As = list(mapint())
    mod = 10**9+7
    pos = []
    neg = []
    for a in As:
        if a>=0:
            pos.append(a)
        else:
            neg.append(a)

    pos.sort(reverse=True)
    neg.sort()
    lenp = len(pos)
    lenn = len(neg)
    if not pos and K%2==1:
        ans = 1
        for i, n in enumerate(neg[::-1]):
            ans *= n
            ans %= mod
            if i==K-1:
                break
        return ans
    if lenp+lenn==K and (K-lenp)%2==1:
        ans = 1
        pos.extend(neg)
        pos.sort(reverse=True)
        for i, p in enumerate(pos):
            ans *= p
            ans %= mod
            if i==K-1:
                break
        return ans
    ans = 1
    pcnt = 0
    ncnt = 0
    for i in range(K//2):
        if pcnt*2+1>=lenp:
            ans *= neg[ncnt*2]*neg[ncnt*2+1]
            ans %= mod
            ncnt += 1
        elif ncnt*2+1>=lenn:
            ans *= pos[pcnt*2]*pos[pcnt*2+1]
            ans %= mod
            pcnt += 1
        elif pos[pcnt*2]*pos[pcnt*2+1]>neg[ncnt*2]*neg[ncnt*2+1]:
            ans *= pos[pcnt*2]*pos[pcnt*2+1]
            ans %= mod
            pcnt += 1
        else:
            ans *= neg[ncnt*2]*neg[ncnt*2+1]
            ans %= mod
            ncnt += 1
    if K%2==1:
        ans *= pos[pcnt*2]
        ans %= mod
    return ans

print(solve())

Buggy python submission (verdict: Runtime Error):
import sys
def input(): return sys.stdin.readline().strip()
def mapint(): return map(int, input().split())
sys.setrecursionlimit(10**9)

def solve():
    N, K = mapint()
    As = list(mapint())
    mod = 10**9+7
    pos = []
    neg = []
    for a in As:
        if a>=0:
            pos.append(a)
        else:
            neg.append(a)
    
    pos.sort(reverse=True)
    neg.sort()
    lenp = len(pos)
    lenn = len(neg)
    if not pos and K%2==1:
        ans = 1
        for i, n in enumerate(neg[::-1]):
            ans *= n
            ans %= mod
            if i==K-1:
                break
        return ans
    if lenp+lenn==K and (K-lenp)%2==1:
        ans = 1
        pos.extend(neg)
        pos.sort(reverse=True)
        for i, p in enumerate(pos):
            ans *= p
            ans %= mod
            if i==K-1:
                break
        return ans
    ans = 1
    pcnt = 0
    ncnt = 0
    for i in range(K//2):
        if pcnt+2>=lenp:
            ans *= neg[ncnt*2]*neg[ncnt*2+1]
            ans %= mod
            ncnt += 1
        elif ncnt+2>=lenn:
            ans *= pos[pcnt*2]*pos[pcnt*2+1]
            ans %= mod
            pcnt += 1
        elif pos[pcnt*2]*pos[pcnt*2+1]>neg[ncnt*2]*neg[ncnt*2+1]:
            ans *= pos[pcnt*2]*pos[pcnt*2+1]
            ans %= mod
            pcnt += 1
        else:
            ans *= neg[ncnt*2]*neg[ncnt*2+1]
            ans %= mod
            ncnt += 1
    if K%2==1:
        ans *= pos[pcnt]
        ans %= mod
    return ans

print(solve())

Fixed submission:
import sys
def input(): return sys.stdin.readline().strip()
def mapint(): return map(int, input().split())
sys.setrecursionlimit(10**9)

def solve():
    N, K = mapint()
    As = list(mapint())
    mod = 10**9+7
    pos = []
    neg = []
    for a in As:
        if a>=0:
            pos.append(a)
        else:
            neg.append(a)

    pos.sort(reverse=True)
    neg.sort()
    lenp = len(pos)
    lenn = len(neg)
    if not pos and K%2==1:
        ans = 1
        for i, n in enumerate(neg[::-1]):
            ans *= n
            ans %= mod
            if i==K-1:
                break
        return ans
    if lenp+lenn==K and (K-lenp)%2==1:
        ans = 1
        pos.extend(neg)
        pos.sort(reverse=True)
        for i, p in enumerate(pos):
            ans *= p
            ans %= mod
            if i==K-1:
                break
        return ans
    ans = 1
    pcnt = 0
    ncnt = 0
    for i in range(K//2):
        if pcnt*2+1>=lenp:
            ans *= neg[ncnt*2]*neg[ncnt*2+1]
            ans %= mod
            ncnt += 1
        elif ncnt*2+1>=lenn:
            ans *= pos[pcnt*2]*pos[pcnt*2+1]
            ans %= mod
            pcnt += 1
        elif pos[pcnt*2]*pos[pcnt*2+1]>neg[ncnt*2]*neg[ncnt*2+1]:
            ans *= pos[pcnt*2]*pos[pcnt*2+1]
            ans %= mod
            pcnt += 1
        else:
            ans *= neg[ncnt*2]*neg[ncnt*2+1]
            ans %= mod
            ncnt += 1
    if K%2==1:
        ans *= pos[pcnt*2]
        ans %= mod
    return ans

print(solve())