Buggy python submission (verdict: Runtime Error):
import math
x,y = map(int,input().split())

def cmb(n, r, mod):
    if ( r<0 or r>n ):
        return 0
    r = min(r, n-r)
    return g1[n] * g2[r] * g2[n-r] % mod

mod = 10**9+7 #出力の制限
N = 10**6
g1 = [1, 1] # 元テーブル
g2 = [1, 1] #逆元テーブル
inverse = [0, 1] #逆元テーブル計算用テーブル

for i in range( 2, N + 1 ):
    g1.append( ( g1[-1] * i ) % mod )
    inverse.append( ( -inverse[mod % i] * (mod//i) ) % mod )
    g2.append( (g2[-1] * inverse[-1]) % mod )

if (x+y)%3!=0:
    print(0)
else:
    a = x-(x+y)//3
    b = y-(x+y)//3
    print(cmb(a+b,a,inf))

Fixed submission:
x, y = map(int, input().split())
if (x+y)%3 != 0:
    print(0)
    exit()

def cmb(n, r, mod):
    if ( r<0 or r>n ):
        return 0
    r = min(r, n-r)
    return g1[n] * g2[r] * g2[n-r] % mod
 
mod = 10**9+7
N = 10**6
g1 = [1, 1]
g2 = [1, 1]
inverse = [0, 1]
 
for i in range( 2, N + 1 ):
    g1.append( ( g1[-1] * i ) % mod )
    inverse.append( ( -inverse[mod % i] * (mod//i) ) % mod )
    g2.append( (g2[-1] * inverse[-1]) % mod )
 
 
a = (2*x-y)//3
b = (2*y-x)//3
n = a+b
r = a
res = cmb(n,r,mod)
print(res)

Buggy python submission (verdict: Runtime Error):
import math
x,y = map(int,input().split())
sum_xy = x+y

def cmb(n, r, mod):
    if ( r<0 or r>n ):
        return 0
    r = min(r, n-r)
    return g1[n] * g2[r] * g2[n-r] % mod

mod = 10**9+7 #出力の制限
N = 10**6
g1 = [1, 1] # 元テーブル
g2 = [1, 1] #逆元テーブル
inverse = [0, 1] #逆元テーブル計算用テーブル

for i in range( 2, N + 1 ):
    g1.append( ( g1[-1] * i ) % mod )
    inverse.append( ( -inverse[mod % i] * (mod//i) ) % mod )
    g2.append( (g2[-1] * inverse[-1]) % mod )

if sum_xy%3!=0:
    print(0)
else:
    ab_sum = sum_xy//3
    a = x-ab_sum
    b = y-ab_sum
    print(cmb(ab_sum,a,inf))

Fixed submission:
x, y = map(int, input().split())
if (x+y)%3 != 0:
    print(0)
    exit()

def cmb(n, r, mod):
    if ( r<0 or r>n ):
        return 0
    r = min(r, n-r)
    return g1[n] * g2[r] * g2[n-r] % mod
 
mod = 10**9+7
N = 10**6
g1 = [1, 1]
g2 = [1, 1]
inverse = [0, 1]
 
for i in range( 2, N + 1 ):
    g1.append( ( g1[-1] * i ) % mod )
    inverse.append( ( -inverse[mod % i] * (mod//i) ) % mod )
    g2.append( (g2[-1] * inverse[-1]) % mod )
 
 
a = (2*x-y)//3
b = (2*y-x)//3
n = a+b
r = a
res = cmb(n,r,mod)
print(res)

Buggy python submission (verdict: Time Limit Exceeded):
import math
x,y = map(int,input().split())
sum_xy = x+y

def cmb(n, r, mod):
    if ( r<0 or r>n ):
        return 0
    r = min(r, n-r)
    return g1[n] * g2[r] * g2[n-r] % mod

mod = 10**9+7 #出力の制限
N = 10**7
g1 = [1, 1] # 元テーブル
g2 = [1, 1] #逆元テーブル
inverse = [0, 1] #逆元テーブル計算用テーブル

for i in range( 2, N + 1 ):
    g1.append( ( g1[-1] * i ) % mod )
    inverse.append( ( -inverse[mod % i] * (mod//i) ) % mod )
    g2.append( (g2[-1] * inverse[-1]) % mod )

if sum_xy%3!=0:
    print(0)
else:
    ab_sum = sum_xy//3
    a = x-ab_sum
    b = y-ab_sum
    print(cmb(ab_sum,a,inf))

Fixed submission:
x, y = map(int, input().split())
if (x+y)%3 != 0:
    print(0)
    exit()

def cmb(n, r, mod):
    if ( r<0 or r>n ):
        return 0
    r = min(r, n-r)
    return g1[n] * g2[r] * g2[n-r] % mod
 
mod = 10**9+7
N = 10**6
g1 = [1, 1]
g2 = [1, 1]
inverse = [0, 1]
 
for i in range( 2, N + 1 ):
    g1.append( ( g1[-1] * i ) % mod )
    inverse.append( ( -inverse[mod % i] * (mod//i) ) % mod )
    g2.append( (g2[-1] * inverse[-1]) % mod )
 
 
a = (2*x-y)//3
b = (2*y-x)//3
n = a+b
r = a
res = cmb(n,r,mod)
print(res)

Buggy python submission (verdict: Runtime Error):
import math
x,y = map(int,input().split())
sum_xy = x+y

def cmb(n, r, mod):
    if ( r<0 or r>n ):
        return 0
    r = min(r, n-r)
    return g1[n] * g2[r] * g2[n-r] % mod

mod = 10**9+7 #出力の制限
N = 8*(10**6)
g1 = [1, 1] # 元テーブル
g2 = [1, 1] #逆元テーブル
inverse = [0, 1] #逆元テーブル計算用テーブル

for i in range( 2, N + 1 ):
    g1.append( ( g1[-1] * i ) % mod )
    inverse.append( ( -inverse[mod % i] * (mod//i) ) % mod )
    g2.append( (g2[-1] * inverse[-1]) % mod )

if sum_xy%3!=0:
    print(0)
else:
    ab_sum = sum_xy//3
    a = x-ab_sum
    b = y-ab_sum
    if a<0 or b<0:
        print(0)
    else:
        print(cmb(ab_sum,a,inf))

Fixed submission:
x, y = map(int, input().split())
if (x+y)%3 != 0:
    print(0)
    exit()

def cmb(n, r, mod):
    if ( r<0 or r>n ):
        return 0
    r = min(r, n-r)
    return g1[n] * g2[r] * g2[n-r] % mod
 
mod = 10**9+7
N = 10**6
g1 = [1, 1]
g2 = [1, 1]
inverse = [0, 1]
 
for i in range( 2, N + 1 ):
    g1.append( ( g1[-1] * i ) % mod )
    inverse.append( ( -inverse[mod % i] * (mod//i) ) % mod )
    g2.append( (g2[-1] * inverse[-1]) % mod )
 
 
a = (2*x-y)//3
b = (2*y-x)//3
n = a+b
r = a
res = cmb(n,r,mod)
print(res)

Buggy python submission (verdict: Runtime Error):
import math
x,y = map(int,input().split())
sum_xy = x+y

def cmb(n, r, mod):
    if ( r<0 or r>n ):
        return 0
    r = min(r, n-r)
    return g1[n] * g2[r] * g2[n-r] % mod

mod = 10**9+7 #出力の制限
N = 10**6
g1 = [1, 1] # 元テーブル
g2 = [1, 1] #逆元テーブル
inverse = [0, 1] #逆元テーブル計算用テーブル

for i in range( 2, N + 1 ):
    g1.append( ( g1[-1] * i ) % mod )
    inverse.append( ( -inverse[mod % i] * (mod//i) ) % mod )
    g2.append( (g2[-1] * inverse[-1]) % mod )

if sum_xy%3!=0:
    print(0)
else:
    ab_sum = sum_xy//3
    a = x-ab_sum
    b = y-ab_sum
    if a<0 or b<0:
        print(0)
    else:
        print(cmb(ab_sum,a,inf))

Fixed submission:
x, y = map(int, input().split())
if (x+y)%3 != 0:
    print(0)
    exit()

def cmb(n, r, mod):
    if ( r<0 or r>n ):
        return 0
    r = min(r, n-r)
    return g1[n] * g2[r] * g2[n-r] % mod
 
mod = 10**9+7
N = 10**6
g1 = [1, 1]
g2 = [1, 1]
inverse = [0, 1]
 
for i in range( 2, N + 1 ):
    g1.append( ( g1[-1] * i ) % mod )
    inverse.append( ( -inverse[mod % i] * (mod//i) ) % mod )
    g2.append( (g2[-1] * inverse[-1]) % mod )
 
 
a = (2*x-y)//3
b = (2*y-x)//3
n = a+b
r = a
res = cmb(n,r,mod)
print(res)

Buggy python submission (verdict: Runtime Error):
import math
x,y = map(int,input().split())
sum_xy = x+y

def cmb(n, r, mod):
    if ( r<0 or r>n ):
        return 0
    r = min(r, n-r)
    return g1[n] * g2[r] * g2[n-r] % mod

mod = 10**9+7 #出力の制限
N = 5*(10**6)
g1 = [1, 1] # 元テーブル
g2 = [1, 1] #逆元テーブル
inverse = [0, 1] #逆元テーブル計算用テーブル

for i in range( 2, N + 1 ):
    g1.append( ( g1[-1] * i ) % mod )
    inverse.append( ( -inverse[mod % i] * (mod//i) ) % mod )
    g2.append( (g2[-1] * inverse[-1]) % mod )

if sum_xy%3!=0:
    print(0)
else:
    ab_sum = sum_xy//3
    a = x-ab_sum
    b = y-ab_sum
    print(cmb(ab_sum,a,inf))
   

Fixed submission:
x, y = map(int, input().split())
if (x+y)%3 != 0:
    print(0)
    exit()

def cmb(n, r, mod):
    if ( r<0 or r>n ):
        return 0
    r = min(r, n-r)
    return g1[n] * g2[r] * g2[n-r] % mod
 
mod = 10**9+7
N = 10**6
g1 = [1, 1]
g2 = [1, 1]
inverse = [0, 1]
 
for i in range( 2, N + 1 ):
    g1.append( ( g1[-1] * i ) % mod )
    inverse.append( ( -inverse[mod % i] * (mod//i) ) % mod )
    g2.append( (g2[-1] * inverse[-1]) % mod )
 
 
a = (2*x-y)//3
b = (2*y-x)//3
n = a+b
r = a
res = cmb(n,r,mod)
print(res)

Buggy python submission (verdict: Time Limit Exceeded):
import math
x,y = map(int,input().split())
sum_xy = x+y

def cmb(n, r, mod):
    if ( r<0 or r>n ):
        return 0
    r = min(r, n-r)
    return g1[n] * g2[r] * g2[n-r] % mod

mod = 10**9+7 #出力の制限
N = 10**7
g1 = [1, 1] # 元テーブル
g2 = [1, 1] #逆元テーブル
inverse = [0, 1] #逆元テーブル計算用テーブル

for i in range( 2, N + 1 ):
    g1.append( ( g1[-1] * i ) % mod )
    inverse.append( ( -inverse[mod % i] * (mod//i) ) % mod )
    g2.append( (g2[-1] * inverse[-1]) % mod )

if sum_xy%3!=0:
    print(0)
else:
    ab_sum = sum_xy//3
    a = x-ab_sum
    b = y-ab_sum
    print(cmb(ab_sum,a,inf))
    


Fixed submission:
x, y = map(int, input().split())
if (x+y)%3 != 0:
    print(0)
    exit()

def cmb(n, r, mod):
    if ( r<0 or r>n ):
        return 0
    r = min(r, n-r)
    return g1[n] * g2[r] * g2[n-r] % mod
 
mod = 10**9+7
N = 10**6
g1 = [1, 1]
g2 = [1, 1]
inverse = [0, 1]
 
for i in range( 2, N + 1 ):
    g1.append( ( g1[-1] * i ) % mod )
    inverse.append( ( -inverse[mod % i] * (mod//i) ) % mod )
    g2.append( (g2[-1] * inverse[-1]) % mod )
 
 
a = (2*x-y)//3
b = (2*y-x)//3
n = a+b
r = a
res = cmb(n,r,mod)
print(res)

Buggy python submission (verdict: Time Limit Exceeded):
import math
x,y = map(int,input().split())
sum_xy = x+y

def cmb(n, r, mod):
    if ( r<0 or r>n ):
        return 0
    r = min(r, n-r)
    return g1[n] * g2[r] * g2[n-r] % mod

mod = 10**9+7 #出力の制限
N = 10**7
g1 = [1, 1] # 元テーブル
g2 = [1, 1] #逆元テーブル
inverse = [0, 1] #逆元テーブル計算用テーブル

for i in range( 2, N + 1 ):
    g1.append( ( g1[-1] * i ) % mod )
    inverse.append( ( -inverse[mod % i] * (mod//i) ) % mod )
    g2.append( (g2[-1] * inverse[-1]) % mod )

if sum_xy%3!=0:
    print(0)
else:
    ab_sum = sum_xy//3
    a = x-ab_sum
    b = y-ab_sum
    print(cmb(ab_sum,a,inf))
    


Fixed submission:
x, y = map(int, input().split())
if (x+y)%3 != 0:
    print(0)
    exit()

def cmb(n, r, mod):
    if ( r<0 or r>n ):
        return 0
    r = min(r, n-r)
    return g1[n] * g2[r] * g2[n-r] % mod
 
mod = 10**9+7
N = 10**6
g1 = [1, 1]
g2 = [1, 1]
inverse = [0, 1]
 
for i in range( 2, N + 1 ):
    g1.append( ( g1[-1] * i ) % mod )
    inverse.append( ( -inverse[mod % i] * (mod//i) ) % mod )
    g2.append( (g2[-1] * inverse[-1]) % mod )
 
 
a = (2*x-y)//3
b = (2*y-x)//3
n = a+b
r = a
res = cmb(n,r,mod)
print(res)

Buggy python submission (verdict: Runtime Error):
import math
x,y = map(int,input().split())
sum_xy = x+y

def cmb(n, r, mod):
    if ( r<0 or r>n ):
        return 0
    r = min(r, n-r)
    return g1[n] * g2[r] * g2[n-r] % mod

mod = 10**9+7 #出力の制限
N = 10**6
g1 = [1, 1] # 元テーブル
g2 = [1, 1] #逆元テーブル
inverse = [0, 1] #逆元テーブル計算用テーブル

for i in range( 2, N + 1 ):
    g1.append( ( g1[-1] * i ) % mod )
    inverse.append( ( -inverse[mod % i] * (mod//i) ) % mod )
    g2.append( (g2[-1] * inverse[-1]) % mod )

if sum_xy%3!=0:
    print(0)
else:
    #a+b
    ab_sum = sum_xy//3
    a = x-ab_sum
    b = y-ab_sum
#     a_kaizyo = 1
#     b_kaizyo = 1
#     ab_kaizyo = 1
#     for i in range(1,a+1):
#         temp =  a_kaizyo*i
#         a_kaizyo = temp%inf
#     for i in range(1,b+1):
#         temp =  b_kaizyo*i
#         b_kaizyo = temp%inf
#     for i in range(1,ab_sum+1):
#         temp =  ab_kaizyo*i
#         ab_kaizyo = temp%inf

    print(cmb(ab_sum,a,inf))
    


Fixed submission:
x, y = map(int, input().split())
if (x+y)%3 != 0:
    print(0)
    exit()

def cmb(n, r, mod):
    if ( r<0 or r>n ):
        return 0
    r = min(r, n-r)
    return g1[n] * g2[r] * g2[n-r] % mod
 
mod = 10**9+7
N = 10**6
g1 = [1, 1]
g2 = [1, 1]
inverse = [0, 1]
 
for i in range( 2, N + 1 ):
    g1.append( ( g1[-1] * i ) % mod )
    inverse.append( ( -inverse[mod % i] * (mod//i) ) % mod )
    g2.append( (g2[-1] * inverse[-1]) % mod )
 
 
a = (2*x-y)//3
b = (2*y-x)//3
n = a+b
r = a
res = cmb(n,r,mod)
print(res)