Buggy python submission (verdict: Time Limit Exceeded):
n = 50000
c = [1 for i in range(n)]
c[0] = 0
i = 2
while i**2 <= n:
    j = i*2
    while j <= n:
        c[j - 1] = 0
        j += i
    i += 1

while True:
    n = int(input())
    if n == 0:
        break
    elif n%2 == 1:
        print(0)
        continue
    cnt = 0
    for i in range(n):
        if c[i] == 1 and c[n-i] == 1:
            cnt +=1
    print(cnt)



Fixed submission:
n = 50001
is_prime = [i for i in range(n)]
is_prime[0] = is_prime[1] = 0
i = 2
while i**2 <= n:
    j = i*2
    while j < n:
        is_prime[j] = 0
        j += i
    i += 1

prime_set  = set(is_prime)
prime_set.remove(0)
prime_list = sorted(list(prime_set))

while True:
    cnt = 0
    n = int(input())
    if n == 0:
        break
    for i in prime_list:
        if i > n//2:
            break
        if n - i in prime_set:
            cnt += 1
    print(cnt)

Buggy python submission (verdict: Time Limit Exceeded):
n = 50000
c = [1 for i in range(n)]
c[0] = 0
i = 2
while i**2 <= n:
    j = i*2
    while j <= n:
        c[j - 1] = 0
        j += i
    i += 1

while True:
    n = int(input())
    if n == 0:
        break
    elif n%2 == 1:
        print(0)
        continue
    cnt = 0
    for i in range(n):
        if c[i] == 1 and c[n-i] == 1:
            cnt +=1
    print(cnt)



Fixed submission:
n = 50001
is_prime = [i for i in range(n)]
is_prime[0] = is_prime[1] = 0
i = 2
while i**2 <= n:
    j = i*2
    while j < n:
        is_prime[j] = 0
        j += i
    i += 1

prime_set  = set(is_prime)
prime_set.remove(0)
prime_list = sorted(list(prime_set))

while True:
    cnt = 0
    n = int(input())
    if n == 0:
        break
    for i in prime_list:
        if i > n//2:
            break
        if n - i in prime_set:
            cnt += 1
    print(cnt)

Buggy python submission (verdict: Time Limit Exceeded):
n = 50000
c = [1 for i in range(n)]
c[0] = 0
i = 2
while i**2 <= n:
    j = i*2
    while j <= n:
        c[j - 1] = 0
        j += i
    i += 1

while True:
    n = int(input())
    if n == 0:
        break
    elif n%2 == 1:
        print(0)
        continue
    cnt = 0
    for i in range(n):
        if c[i] == 1 and c[n-i] == 1:
            cnt +=1
    print(cnt)



Fixed submission:
n = 50001
is_prime = [i for i in range(n)]
is_prime[0] = is_prime[1] = 0
i = 2
while i**2 <= n:
    j = i*2
    while j < n:
        is_prime[j] = 0
        j += i
    i += 1

prime_set  = set(is_prime)
prime_set.remove(0)
prime_list = sorted(list(prime_set))

while True:
    cnt = 0
    n = int(input())
    if n == 0:
        break
    for i in prime_list:
        if i > n//2:
            break
        if n - i in prime_set:
            cnt += 1
    print(cnt)

Buggy python submission (verdict: Time Limit Exceeded):
n = 50001
c = [1 for i in range(n)]
c[0] = 0
i = 2
while i**2 <= n:
    j = i*2
    while j <= n:
        c[j - 1] = 0
        j += i
    i += 1

while True:
    n = int(input())
    if n == 0:
        break
    elif n%2 == 1:
        print(0)
        continue
    cnt = 0
    for i in range(n):
        if c[i] == 1 and c[n-i] == 1:
            cnt +=1
    print(cnt)



Fixed submission:
n = 50001
is_prime = [i for i in range(n)]
is_prime[0] = is_prime[1] = 0
i = 2
while i**2 <= n:
    j = i*2
    while j < n:
        is_prime[j] = 0
        j += i
    i += 1

prime_set  = set(is_prime)
prime_set.remove(0)
prime_list = sorted(list(prime_set))

while True:
    cnt = 0
    n = int(input())
    if n == 0:
        break
    for i in prime_list:
        if i > n//2:
            break
        if n - i in prime_set:
            cnt += 1
    print(cnt)

Buggy python submission (verdict: Runtime Error):
n = 50001
c = [1 for i in range(n)]
c[0] = 0
i = 2
while i**2 <= n:
    j = i*2
    while j <= n:
        c[j - 1] = 0
        j += i
    i += 1

while True:
    n = int(input())
    if n == 0:
        break
    elif n%2 == 1:
        print(0)
        continue
    cnt = 0
    for i in range(n/2):
        if c[i] == 1 and c[n-i] == 1:
            cnt +=1
    print(cnt)



Fixed submission:
n = 50001
is_prime = [i for i in range(n)]
is_prime[0] = is_prime[1] = 0
i = 2
while i**2 <= n:
    j = i*2
    while j < n:
        is_prime[j] = 0
        j += i
    i += 1

prime_set  = set(is_prime)
prime_set.remove(0)
prime_list = sorted(list(prime_set))

while True:
    cnt = 0
    n = int(input())
    if n == 0:
        break
    for i in prime_list:
        if i > n//2:
            break
        if n - i in prime_set:
            cnt += 1
    print(cnt)

Buggy python submission (verdict: Time Limit Exceeded):
n = 50001
c = [1 for i in range(n)]
c[0] = 0
i = 2
while i**2 <= n:
    j = i*2
    while j <= n:
        c[j - 1] = 0
        j += i
    i += 1

while True:
    n = int(input())
    if n == 0:
        break
    elif n%2 == 1:
        print(0)
        continue
    cnt = 0
    for i in range(n//2):
        if c[i] == 1 and c[n-i] == 1:
            cnt +=1
    print(cnt)



Fixed submission:
n = 50001
is_prime = [i for i in range(n)]
is_prime[0] = is_prime[1] = 0
i = 2
while i**2 <= n:
    j = i*2
    while j < n:
        is_prime[j] = 0
        j += i
    i += 1

prime_set  = set(is_prime)
prime_set.remove(0)
prime_list = sorted(list(prime_set))

while True:
    cnt = 0
    n = int(input())
    if n == 0:
        break
    for i in prime_list:
        if i > n//2:
            break
        if n - i in prime_set:
            cnt += 1
    print(cnt)

Buggy python submission (verdict: Time Limit Exceeded):
n = 50001
c = [1 for i in range(n)]
c[0] = 0
i = 2
while i**2 <= n:
    j = i*2
    while j <= n:
        c[j - 1] = 0
        j += i
    i += 1

while True:
    n = int(input())
    if n == 0:
        break
    elif n%2 == 1:
        print(0)
        continue
    cnt = 0
    for i in range(n//2):
        if c[i] == 1 and c[n-i] == 1:
            cnt +=1
    print(cnt)



Fixed submission:
n = 50001
is_prime = [i for i in range(n)]
is_prime[0] = is_prime[1] = 0
i = 2
while i**2 <= n:
    j = i*2
    while j < n:
        is_prime[j] = 0
        j += i
    i += 1

prime_set  = set(is_prime)
prime_set.remove(0)
prime_list = sorted(list(prime_set))

while True:
    cnt = 0
    n = int(input())
    if n == 0:
        break
    for i in prime_list:
        if i > n//2:
            break
        if n - i in prime_set:
            cnt += 1
    print(cnt)

Buggy python submission (verdict: Time Limit Exceeded):
n = 50000
c = [1 for i in range(n)]
c[0] = 0
i = 2
while i**2 <= n:
    j = i*2
    while j <= n:
        c[j - 1] = 0
        j += i
    i += 1

while True:
    n = int(input())
    cnt = 0
    if n == 0:
        break
    elif n%2 == 0:
        for i in range(n//2):
            if c[i] == 1 and c[n-i] == 1:
                cnt +=1
    print(cnt*2)



Fixed submission:
n = 50001
is_prime = [i for i in range(n)]
is_prime[0] = is_prime[1] = 0
i = 2
while i**2 <= n:
    j = i*2
    while j < n:
        is_prime[j] = 0
        j += i
    i += 1

prime_set  = set(is_prime)
prime_set.remove(0)
prime_list = sorted(list(prime_set))

while True:
    cnt = 0
    n = int(input())
    if n == 0:
        break
    for i in prime_list:
        if i > n//2:
            break
        if n - i in prime_set:
            cnt += 1
    print(cnt)

Buggy python submission (verdict: Time Limit Exceeded):
n = 50000
c = [1 for i in range(n)]
c[0] = 0
i = 2
while i**2 <= n:
    j = i*2
    while j <= n:
        c[j - 1] = 0
        j += i
    i += 1

while True:
    n = int(input())
    cnt = 0
    if n == 0:
        break
    elif n%2 == 0:
        for i in range(0, n//2, 2):
            if c[i] == 1 and c[n-i-2] == 1:
                cnt +=1
    print(cnt*2)



Fixed submission:
n = 50001
is_prime = [i for i in range(n)]
is_prime[0] = is_prime[1] = 0
i = 2
while i**2 <= n:
    j = i*2
    while j < n:
        is_prime[j] = 0
        j += i
    i += 1

prime_set  = set(is_prime)
prime_set.remove(0)
prime_list = sorted(list(prime_set))

while True:
    cnt = 0
    n = int(input())
    if n == 0:
        break
    for i in prime_list:
        if i > n//2:
            break
        if n - i in prime_set:
            cnt += 1
    print(cnt)

Buggy python submission (verdict: Time Limit Exceeded):
n = 50001
is_prime = [True for i in range(n)]
is_prime[0] = is_prime[1] = False
i = 2
while i**2 <= n:
    j = i*2
    while j < n:
        is_prime[j] = False
        j += i
    i += 1

cnt_pair = [0 for i in range(n)]
for i in range(n):
    cnt = 0
    if i%2 == 0:
        for j in range(n):
            if is_prime[j] and is_prime[n - j]:
                cnt += 1
        cnt_pair[i] = cnt

while True:
    n = int(input())
    if n == 0:
        break
    print(cnt_pair[n])



Fixed submission:
n = 50001
is_prime = [i for i in range(n)]
is_prime[0] = is_prime[1] = 0
i = 2
while i**2 <= n:
    j = i*2
    while j < n:
        is_prime[j] = 0
        j += i
    i += 1

prime_set  = set(is_prime)
prime_set.remove(0)
prime_list = sorted(list(prime_set))

while True:
    cnt = 0
    n = int(input())
    if n == 0:
        break
    for i in prime_list:
        if i > n//2:
            break
        if n - i in prime_set:
            cnt += 1
    print(cnt)

Buggy python submission (verdict: Time Limit Exceeded):
n = 50001
is_prime = [True for i in range(n)]
is_prime[0] = is_prime[1] = False
i = 2
while i**2 <= n:
    j = i*2
    while j < n:
        is_prime[j] = False
        j += i
    i += 1

cnt_pair = [0 for i in range(n)]
for i in range(n):
    cnt = 0
    if i%2 == 0:
        for j in range(0, n//2):
            if is_prime[j] and is_prime[n - j]:
                cnt += 1
        cnt_pair[i] = cnt

while True:
    n = int(input())
    if n == 0:
        break
    print(cnt_pair[n])



Fixed submission:
n = 50001
is_prime = [i for i in range(n)]
is_prime[0] = is_prime[1] = 0
i = 2
while i**2 <= n:
    j = i*2
    while j < n:
        is_prime[j] = 0
        j += i
    i += 1

prime_set  = set(is_prime)
prime_set.remove(0)
prime_list = sorted(list(prime_set))

while True:
    cnt = 0
    n = int(input())
    if n == 0:
        break
    for i in prime_list:
        if i > n//2:
            break
        if n - i in prime_set:
            cnt += 1
    print(cnt)

Buggy python submission (verdict: Time Limit Exceeded):
n = 50001
is_prime = [True for i in range(n)]
is_prime[0] = is_prime[1] = False
i = 2
while i**2 <= n:
    j = i*2
    while j < n:
        is_prime[j] = False
        j += i
    i += 1

cnt_pair = [0 for i in range(n)]
for i in range(n):
    if is_prime[i]:
        for j in range(i, n):
           if i + j >= n:
               break
           if is_prime[j]:
               cnt_pair[i + j] += 1

while True:
    n = int(input())
    if n == 0:
        break
    print(cnt_pair[n])



Fixed submission:
n = 50001
is_prime = [i for i in range(n)]
is_prime[0] = is_prime[1] = 0
i = 2
while i**2 <= n:
    j = i*2
    while j < n:
        is_prime[j] = 0
        j += i
    i += 1

prime_set  = set(is_prime)
prime_set.remove(0)
prime_list = sorted(list(prime_set))

while True:
    cnt = 0
    n = int(input())
    if n == 0:
        break
    for i in prime_list:
        if i > n//2:
            break
        if n - i in prime_set:
            cnt += 1
    print(cnt)

Buggy python submission (verdict: Runtime Error):
n = 30000
is_prime = [True for i in range(n)]
is_prime[0] = is_prime[1] = False
i = 2
while i**2 <= n:
    j = i*2
    while j < n:
        is_prime[j] = False
        j += i
    i += 1

cnt_pair = [0 for i in range(n)]
for i in range(n):
    if is_prime[i]:
        for j in range(i, n):
           if i + j >= n:
               break
           if is_prime[j]:
               cnt_pair[i + j] += 1

while True:
    n = int(input())
    if n == 0:
        break
    print(cnt_pair[n])



Fixed submission:
n = 50001
is_prime = [i for i in range(n)]
is_prime[0] = is_prime[1] = 0
i = 2
while i**2 <= n:
    j = i*2
    while j < n:
        is_prime[j] = 0
        j += i
    i += 1

prime_set  = set(is_prime)
prime_set.remove(0)
prime_list = sorted(list(prime_set))

while True:
    cnt = 0
    n = int(input())
    if n == 0:
        break
    for i in prime_list:
        if i > n//2:
            break
        if n - i in prime_set:
            cnt += 1
    print(cnt)

Buggy python submission (verdict: Time Limit Exceeded):
n = 50001
is_prime = [True for i in range(n)]
is_prime[0] = is_prime[1] = False
i = 2
while i**2 <= n:
    j = i*2
    while j < n:
        is_prime[j] = False
        j += i
    i += 1

cnt_pair = [0 for i in range(n)]
for i in range(n):
    if is_prime[i]:
        for j in range(i, n):
           if i + j >= n:
               break
           if is_prime[j]:
               cnt_pair[i + j] += 1

while True:
    n = int(input())
    if n == 0:
        break
    print(cnt_pair[n])



Fixed submission:
n = 50001
is_prime = [i for i in range(n)]
is_prime[0] = is_prime[1] = 0
i = 2
while i**2 <= n:
    j = i*2
    while j < n:
        is_prime[j] = 0
        j += i
    i += 1

prime_set  = set(is_prime)
prime_set.remove(0)
prime_list = sorted(list(prime_set))

while True:
    cnt = 0
    n = int(input())
    if n == 0:
        break
    for i in prime_list:
        if i > n//2:
            break
        if n - i in prime_set:
            cnt += 1
    print(cnt)

Buggy python submission (verdict: Time Limit Exceeded):
n = 50001
is_prime = [True for i in range(n)]
is_prime[0] = is_prime[1] = False
i = 2
while i**2 <= n:
    j = i*2
    while j < n:
        is_prime[j] = False
        j += i
    i += 1

cnt_pair = [0 for i in range(n)]
for i in range(n//2):
    if is_prime[i]:
        for j in range(i, n - i):
           if is_prime[j]:
               cnt_pair[i + j] += 1

while True:
    n = int(input())
    if n == 0:
        break
    print(cnt_pair[n])



Fixed submission:
n = 50001
is_prime = [i for i in range(n)]
is_prime[0] = is_prime[1] = 0
i = 2
while i**2 <= n:
    j = i*2
    while j < n:
        is_prime[j] = 0
        j += i
    i += 1

prime_set  = set(is_prime)
prime_set.remove(0)
prime_list = sorted(list(prime_set))

while True:
    cnt = 0
    n = int(input())
    if n == 0:
        break
    for i in prime_list:
        if i > n//2:
            break
        if n - i in prime_set:
            cnt += 1
    print(cnt)

Buggy python submission (verdict: Time Limit Exceeded):
n = 50001
is_prime = [True for i in range(n)]
is_prime[0] = is_prime[1] = False
i = 2
while i**2 <= n:
    j = i*2
    while j < n:
        is_prime[j] = False
        j += i
    i += 1

cnt_pair = [0 for i in range(n)]
for i in range(3, n//2, 2):
    if is_prime[i]:
        for j in range(i, n - i, 2):
           if is_prime[j]:
               cnt_pair[i + j] += 1

while True:
    n = int(input())
    if n == 0:
        break
    print(cnt_pair[n])



Fixed submission:
n = 50001
is_prime = [i for i in range(n)]
is_prime[0] = is_prime[1] = 0
i = 2
while i**2 <= n:
    j = i*2
    while j < n:
        is_prime[j] = 0
        j += i
    i += 1

prime_set  = set(is_prime)
prime_set.remove(0)
prime_list = sorted(list(prime_set))

while True:
    cnt = 0
    n = int(input())
    if n == 0:
        break
    for i in prime_list:
        if i > n//2:
            break
        if n - i in prime_set:
            cnt += 1
    print(cnt)