Buggy python submission (verdict: Time Limit Exceeded):
cij =[]
for i in range(3):
    cij.append(list(map(int, input().split(" "))))

bi_list = []
for b1 in range(-500000, 500000):
    b2 = b1 - (cij[0][0] - cij[0][1])
    b3 = b1 - (cij[0][0] - cij[0][2])

    a1 = cij[0][0]+cij[0][1]+cij[0][2] -b1-b2-b3
    a2 = cij[1][0]+cij[1][1]+cij[1][2] -b1-b2-b3
    a3 = cij[2][0]+cij[2][1]+cij[2][2] -b1-b2-b3
    if a1/3+b1 ==cij[0][0] and a1/3+b2 ==cij[0][1] and a1/3+b3 ==cij[0][2] and a2/3+b1 ==cij[1][0] and a2/3+b2 ==cij[1][1] and a2/3+b3 ==cij[1][2] and a3/3+b1 ==cij[2][0] and a3/3+b2 ==cij[2][1] and a3/3+b3 ==cij[2][2]:
            print("Yes")
            exit()

print("No")

Fixed submission:
cij =[]
for i in range(3):
    cij.append(list(map(int, input().split(" "))))

bi_list = []
for b1 in range(-50000, 50000):
    b2 = b1 - (cij[0][0] - cij[0][1])
    b3 = b1 - (cij[0][0] - cij[0][2])

    a1 = cij[0][0]+cij[0][1]+cij[0][2] -b1-b2-b3
    a2 = cij[1][0]+cij[1][1]+cij[1][2] -b1-b2-b3
    a3 = cij[2][0]+cij[2][1]+cij[2][2] -b1-b2-b3
    if a1/3+b1 ==cij[0][0] and a1/3+b2 ==cij[0][1] and a1/3+b3 ==cij[0][2] and a2/3+b1 ==cij[1][0] and a2/3+b2 ==cij[1][1] and a2/3+b3 ==cij[1][2] and a3/3+b1 ==cij[2][0] and a3/3+b2 ==cij[2][1] and a3/3+b3 ==cij[2][2]:
            print("Yes")
            exit()

print("No")

Buggy python submission (verdict: Runtime Error):
cij =[]
for i in range(3):
    cij.append(list(map(int, input().split(" "))))

bi_list = []
for b1 in range(-500000, 500000):
    b2 = b1 - (cij[0][0] - cij[0][1])
    b3 = b1 - (cij[0][0] - cij[0][2])

    a1 = cij[0][0]+cij[0][1]+cij[0][2] -b1-bi2-b3
    a2 = cij[1][0]+cij[1][1]+cij[1][2] -b1-b2-b3
    a3 = cij[2][0]+cij[2][1]+cij[2][2] -b1-b2-b3
    if (a1) % 3 == 0 and (a2) % 3 == 0 and (a3) % 3 == 0:
        print("Yes")
        exit()

print("No")


Fixed submission:
cij =[]
for i in range(3):
    cij.append(list(map(int, input().split(" "))))

bi_list = []
for b1 in range(-50000, 50000):
    b2 = b1 - (cij[0][0] - cij[0][1])
    b3 = b1 - (cij[0][0] - cij[0][2])

    a1 = cij[0][0]+cij[0][1]+cij[0][2] -b1-b2-b3
    a2 = cij[1][0]+cij[1][1]+cij[1][2] -b1-b2-b3
    a3 = cij[2][0]+cij[2][1]+cij[2][2] -b1-b2-b3
    if a1/3+b1 ==cij[0][0] and a1/3+b2 ==cij[0][1] and a1/3+b3 ==cij[0][2] and a2/3+b1 ==cij[1][0] and a2/3+b2 ==cij[1][1] and a2/3+b3 ==cij[1][2] and a3/3+b1 ==cij[2][0] and a3/3+b2 ==cij[2][1] and a3/3+b3 ==cij[2][2]:
            print("Yes")
            exit()

print("No")

Buggy python submission (verdict: Runtime Error):
cij =[]
for i in range(3):
    cij.append(list(map(int, input().split(" "))))

bi_list = []
for b1 in range(100):
    b2 = b1 - (cij[0][0] - cij[0][1])
    b3 = b1 - (cij[0][0] - cij[0][2])
    if b2 < 0 or b3 < 0 or b2 > cij[0][1] or b3 > cij[0][2] :
        continue
    bi_list.append([b1, b2, b3])

for bi in bi_list:
    a1 = cij[0][0]+cij[0][1]+cij[0][2] -bi[0]-bi[1]-bi[2] 
a2 = cij[1][0]+cij[1][1]+cij[1][2] -bi[0]-bi[1]-bi[2] 
a3 = cij[2][0]+cij[2][1]+cij[2][2] -bi[0]-bi[1]-bi[2] 
    if (a1) % 3 == 0 and (a2) % 3 == 0 and (a3) % 3 == 0 and a1 >=0 and a2 >= 0 and a3 >= 0:
        print("Yes")
        exit()

print("No")

Fixed submission:
cij =[]
for i in range(3):
    cij.append(list(map(int, input().split(" "))))

bi_list = []
for b1 in range(-50000, 50000):
    b2 = b1 - (cij[0][0] - cij[0][1])
    b3 = b1 - (cij[0][0] - cij[0][2])

    a1 = cij[0][0]+cij[0][1]+cij[0][2] -b1-b2-b3
    a2 = cij[1][0]+cij[1][1]+cij[1][2] -b1-b2-b3
    a3 = cij[2][0]+cij[2][1]+cij[2][2] -b1-b2-b3
    if a1/3+b1 ==cij[0][0] and a1/3+b2 ==cij[0][1] and a1/3+b3 ==cij[0][2] and a2/3+b1 ==cij[1][0] and a2/3+b2 ==cij[1][1] and a2/3+b3 ==cij[1][2] and a3/3+b1 ==cij[2][0] and a3/3+b2 ==cij[2][1] and a3/3+b3 ==cij[2][2]:
            print("Yes")
            exit()

print("No")