a = []
for i in range(8):
    a.append(list(map(int, input().split())))
for i in range(7):
    mult = True
    for j in range(7):
        if a[i][j] // abs(a[i][j]) != a[i][j + 1] // abs(a[i][j + 1]):
            mult = False
    if mult == True:
        continue
    else:
        for j in range(8):
            if a[i][j] < 0:
                tmp1 = a[i + 1][j]
                tmp2 = a[i][j]
                a[i][j] = tmp1
                a[i + 1][j] = tmp2
                mult1 = True
                for k in range(7):
                    if a[i][k] // abs(a[i][k]) != a[i][k + 1] // abs(a[i][k + 1]):
                        mult1 = False
                if mult1 == True:
                    break
mult2 = []
for i in range(8):
    multc = True
    for j in range(7):
        if a[i][j] // abs(a[i][j]) != a[i][j + 1] // abs(a[i][j + 1]):
            multc = False
            mult2.append(multc)
    if multc == False:
        print("NO")
        break
if False not in mult2:
    print("YES")