Problem: There are N people numbered 1 to N. Each of them is either an _honest_ person whose testimonies are always correct or an _unkind_ person whose testimonies may be correct or not.  Person i gives A_i testimonies. The j-th testimony by Person i is represented by two integers x_{ij} and y_{ij}. If y_{ij} = 1, the testimony says Person x_{ij} is honest; if y_{ij} = 0, it says Person x_{ij} is unkind.  How many honest persons can be among those N people at most?

Submission attempts (in order):
n = int(input())

sayTable = []
for i in range(n):
	a = int(input())
	
	sayArray = []
	for j in range(a):
		x, y = [int(v) for v in input().split()]
		sayArray.append((x-1, y+1))
	sayTable.append(sayArray)

def count(honest):
	count = 0
	for v in honest:
		if v == 2:
			count += 1
	return count

def checkHonest(sayArray, honest):
	for x, y in sayArray:
		if y == 2 and honest[x] != 2:
			return False
	return True

def checkHonestAll(sayTable, honest):
	for i in range(n):
		h = honest[i]
		if h != 2:
			continue
        sayArray = sayTable[i]
		for x, y in sayArray:
			if y != honest[x]:
				return False
	return True

def setHonest(sayArray, honest):
	for x, y in sayArray:
		honest[x] = y

def search(sayTable, honest, i):
	if i >= n;
		if checkHonestAll(sayTable, honest):
			return count(honest)
		else:
			return 0

	count = 0
	h = honest[i]
    sayArray = sayTable[i]
	if (h == 0 or h == 2) and checkHonest(sayArray, honest):
		copyHonest = honest[:]
		setHonest(sayArray, copyHonest)
		copyHonest[i] = 2
		c = search(sayTable, copyHonest, i+1)
		if count < c:
			count = c

	honest[i] = 1
	c = search(sayTable, honest, i+1)
	if count < c:
		count = c
	return count

print(search(sayTable, [0] * n, 0));


n = int(input())

sayTable = []
for i in range(n):
	a = int(input())
	
	sayArray = []
	for j in range(a):
		x, y = [int(v) for v in input().split()]
		sayArray.append((x-1, y+1))
	sayTable.append(sayArray)

def count(honest):
	count = 0
	for v in honest:
		if v == 2:
			count += 1
	return count

def checkHonest(sayArray, honest):
	for x, y in sayArray:
		if y == 2 and honest[x] != 2:
			return False
	return True

def checkHonestAll(sayTable, honest):
	for i in range(n):
		h = honest[i]
		if h != 2:
			continue
		for x, y in sayArray:
		if honest[x] != y:
			return False
	return True

def setHonest(sayArray, honest):
	for x, y in sayArray:
		honest[x] = y

def search(sayTable, honest, i):
	if i >= n;
		if checkHonestAll(sayTable, honest):
			return count(honest)
		else:
			return 0

	count = 0
	h = honest[i]
	if (h == 0 or h == 2) and checkHonest(sayTable, honest):
		copyHonest = honest[:]
		setHonest(copyHonest, sayTable[i])
		copyHonest[i] = 2
		c = search(sayTable, copyHonest, i + 1)
		if count < c:
			count = c

	honest[i] = 1
	c = search(sayTable, honest, i+1)
		if count < c:
			count = c
	return count

print(search(sayTable, [0] * n, 0));



n = int(input())

sayTable = []
for i in range(n):
	a = int(input())
	
	sayArray = []
	for j in range(a):
		x, y = [int(v) for v in input().split()]
		sayArray.append((x-1, y+1))
	sayTable.append(sayArray)

def count(honest):
	count = 0
	for v in honest:
		if v == 2:
			count += 1
	return count

def checkHonest(sayArray, honest):
	for x, y in sayArray:
		if y == 2 and honest[x] != 2:
			return False
	return True

def checkHonestAll(sayTable, honest):
	for i in range(n):
		h = honest[i]
		if h != 2:
			continue
		for x, y in sayArray:
			if honest[x] != y:
				return False
	return True

def setHonest(sayArray, honest):
	for x, y in sayArray:
		honest[x] = y

def search(sayTable, honest, i):
	if i >= n;
		if checkHonestAll(sayTable, honest):
			return count(honest)
		else:
			return 0

	count = 0
	h = honest[i]
    sayArray = sayTable[i]
	if (h == 0 or h == 2) and checkHonest(sayArray, honest):
		copyHonest = honest[:]
		setHonest(sayArray, copyHonest)
		copyHonest[i] = 2
		c = search(sayTable, copyHonest, i + 1)
		if count < c:
			count = c

	honest[i] = 1
	c = search(sayTable, honest, i+1)
	if count < c:
		count = c
	return count

print(search(sayTable, [0] * n, 0));


n = int(input())

sayTable = []
for i in range(n):
	a = int(input())
	
	sayArray = []
	for j in range(a):
		x, y = [int(v) for v in input().split()]
		sayArray.append((x-1, y+1))
	sayTable.append(sayArray)

def count(honest):
	count = 0
	for v in honest:
		if v == 2:
			count += 1
	return count

def checkHonest(sayArray, honest):
	for x, y in sayArray:
		if y == 2 and honest[x] != 2:
			return False
	return True

def checkHonestAll(sayTable, honest):
	for i in range(n):
		h = honest[i]
		if h != 2:
			continue
		sayArray = sayTable[i]
		for x, y in sayArray:
			if y != honest[x]:
				return False
	return True

def setHonest(sayArray, honest):
	for x, y in sayArray:
		honest[x] = y

def search(sayTable, honest, i):
	if i >= n;
		if checkHonestAll(sayTable, honest):
			return count(honest)
		else:
			return 0

	count = 0
	h = honest[i]
    sayArray = sayTable[i]
	if (h == 0 or h == 2) and checkHonest(sayArray, honest):
		copyHonest = honest[:]
		setHonest(sayArray, copyHonest)
		copyHonest[i] = 2
		c = search(sayTable, copyHonest, i+1)
		if count < c:
			count = c

	honest[i] = 1
	c = search(sayTable, honest, i+1)
	if count < c:
		count = c
	return count

print(search(sayTable, [0] * n, 0));


n = int(input())

sayTable = []
for i in range(n):
	a = int(input())
	
	sayArray = []
	for j in range(a):
		x, y = [int(v) for v in input().split()]
		sayArray.append((x-1, y+1))
	sayTable.append(sayArray)

def count(honest):
	count = 0
	for v in honest:
		if v == 2:
			count += 1
	return count

def checkHonest(sayArray, honest):
	for x, y in sayArray:
		if y == 2 and honest[x] != 2:
			return False
	return True

def checkHonestAll(sayTable, honest):
	for i in range(n):
		h = honest[i]
		if h != 2:
			continue
        sayArray = sayTable[i]
		for x, y in sayArray:
			if y != honest[x] != y:
				return False
	return True

def setHonest(sayArray, honest):
	for x, y in sayArray:
		honest[x] = y

def search(sayTable, honest, i):
	if i >= n;
		if checkHonestAll(sayTable, honest):
			return count(honest)
		else:
			return 0

	count = 0
	h = honest[i]
    sayArray = sayTable[i]
	if (h == 0 or h == 2) and checkHonest(sayArray, honest):
		copyHonest = honest[:]
		setHonest(sayArray, copyHonest)
		copyHonest[i] = 2
		c = search(sayTable, copyHonest, i + 1)
		if count < c:
			count = c

	honest[i] = 1
	c = search(sayTable, honest, i+1)
	if count < c:
		count = c
	return count

print(search(sayTable, [0] * n, 0));


n = int(input())

sayTable = []
for i in range(n):
	a = int(input())
	
	sayArray = []
	for j in range(a):
		x, y = [int(v) for v in input().split()]
		sayArray.append((x-1, y+1))
sayTable.append(sayArray)

def count(honest):
	count = 0
	for v in honest:
		if v == 2:
			count += 1
	return count

def checkHonest(sayArray, honest):
	for x, y in sayArray:
		if y == 2 and honest[x] != 2:
return False
	return True

def checkHonestAll(sayTable, honest):
	for i in range(n):
		h = honest[i]
		if h != 2:
			continue
		for x, y in sayArray:
		if honest[x] != y:
return False
	return True

def setHonest(sayArray, honest):
	for x, y in sayArray:
		honest[x] = y

def search(sayTable, honest, i):
	if i >= n;
		if checkHonestAll(sayTable, honest):
return count(honest)
else:
	return 0

count = 0
h = honest[i]
if (h == 0 or h == 2) and checkHonest(sayTable, honest):
copyHonest = honest[:]
setHonest(honest, sayTable[i])
copyHonest[i] = 2
c = search(sayTable, copyHonest, i + 1)
if count < c:
	count = c

honest[i] = 1
c = search(sayTable, honest, i+1)
	if count < c:
		count = c
return count

print(search(sayTable, [0] * n, 0));

n = int(input())

sayTable = []
for i in range(n):
	a = int(input())
	
	sayArray = []
	for j in range(a):
		x, y = [int(v) for v in input().split()]
		sayArray.append((x-1, y+1))
sayTable.append(sayArray)

def count(honest):
	count = 0
	for v in honest:
		if v == 2:
			count += 1
	return count

def checkHonest(sayArray, honest):
	for x, y in sayArray:
		if say != 2:
			continue
		if say != honest[x]:
			return False
	return True

def checkHonestAll(sayTable, honest):
	for i in range(n):
		h = honest[i]
		if h != 2:
			continue
		if not checkHonest(sayTable[i]):
			return False
	return True









def search(sayTable, honest, i):
	if i >= n;
		if checkHonestAll(sayTable, honest):
return count(honest)
else:
	return 0

count = 0
h = honest[i]
if (h == 0 or h == 2) and checkHonest(sayTable, honest):
copyHonest = honest[:]
copyHonest[i] = 2
c = search(sayTable, copyHonest, i + 1)
if count < c:
	count = c

honest[i] = 1
c = search(sayTable, honest, i+1)
	if count < c:
		count = c
return count

print(search(sayTable, [0] * n, 0));



n = int(input())

sayTable = []
for i in range(n):
	a = int(input())
	
	sayArray = []
	for j in range(a):
		x, y = [int(v) for v in input().split()]
		sayArray.append((x-1, y+1))
	sayTable.append(sayArray)

def countHonest(honest):
	count = 0
	for v in honest:
		if v == 2:
			count += 1
	return count

def checkHonest(sayArray, honest):
	for x, y in sayArray:
		if y == 2 and honest[x] != 2:
			return False
	return True

def checkHonestAll(sayTable, honest):
	for i in range(n):
		h = honest[i]
		if h != 2:
			continue
		sayArray = sayTable[i]
		for x, y in sayArray:
			if y != honest[x]:
				return False
	return True

def setHonest(sayArray, honest):
	for x, y in sayArray:
		honest[x] = y

def search(sayTable, honest, i):
	if i >= n:
		if checkHonestAll(sayTable, honest):
			return countHonest(honest)
		else:
			return 0

	count = 0
	h = honest[i]
	sayArray = sayTable[i]
	if (h == 0 or h == 2) and checkHonest(sayArray, honest):
		copyHonest = honest[:]
		setHonest(sayArray, copyHonest)
		copyHonest[i] = 2
		c = search(sayTable, copyHonest, i+1)
		if count < c:
			count = c

	honest[i] = 1
	c = search(sayTable, honest, i+1)
	if count < c:
		count = c
	return count

print(search(sayTable, [0] * n, 0))


n = int(input())

sayTable = []
for i in range(n):
	a = int(input())
	
	sayArray = []
	for j in range(a):
		x, y = [int(v) for v in input().split()]
		sayArray.append((x-1, y+1))
	sayTable.append(sayArray)

def count(honest):
	count = 0
	for v in honest:
		if v == 2:
			count += 1
	return count

def checkHonest(sayArray, honest):
	for x, y in sayArray:
		if y == 2 and honest[x] != 2:
			return False
	return True

def checkHonestAll(sayTable, honest):
	for i in range(n):
		h = honest[i]
		if h != 2:
			continue
		for x, y in sayArray:
		if honest[x] != y:
			return False
	return True

def setHonest(sayArray, honest):
	for x, y in sayArray:
		honest[x] = y

def search(sayTable, honest, i):
	if i >= n;
		if checkHonestAll(sayTable, honest):
			return count(honest)
		else:
			return 0

	count = 0
	h = honest[i]
    sayArray = sayTable[i]
	if (h == 0 or h == 2) and checkHonest(sayArray, honest):
		copyHonest = honest[:]
		setHonest(sayArray, copyHonest)
		copyHonest[i] = 2
		c = search(sayTable, copyHonest, i + 1)
		if count < c:
			count = c

	honest[i] = 1
	c = search(sayTable, honest, i+1)
	if count < c:
		count = c
	return count

print(search(sayTable, [0] * n, 0));


n = int(input())

sayTable = []
for i in range(n):
	a = int(input())
	
	sayArray = []
	for j in range(a):
		x, y = [int(v) for v in input().split()]
		sayArray.append((x-1, y+1))
	sayTable.append(sayArray)

def count(honest):
	count = 0
	for v in honest:
		if v == 2:
			count += 1
	return count

def checkHonest(sayArray, honest):
	for x, y in sayArray:
		if y == 2 and honest[x] != 2:
			return False
	return True

def checkHonestAll(sayTable, honest):
	for i in range(n):
		h = honest[i]
		if h != 2:
			continue
		sayArray = sayTable[i]
		for x, y in sayArray:
			if y != honest[x]:
				return False
	return True

def setHonest(sayArray, honest):
	for x, y in sayArray:
		honest[x] = y

def search(sayTable, honest, i):
	if i >= n:
		if checkHonestAll(sayTable, honest):
			return count(honest)
		else:
			return 0

	count = 0
	h = honest[i]
    sayArray = sayTable[i]
	if (h == 0 or h == 2) and checkHonest(sayArray, honest):
		copyHonest = honest[:]
		setHonest(sayArray, copyHonest)
		copyHonest[i] = 2
		c = search(sayTable, copyHonest, i+1)
		if count < c:
			count = c

	honest[i] = 1
	c = search(sayTable, honest, i+1)
	if count < c:
		count = c
	return count

print(search(sayTable, [0] * n, 0));


n = int(input())

sayTable = []
for i in range(n):
	a = int(input())
	
	sayArray = []
	for j in range(a):
		x, y = [int(v) for v in input().split()]
		sayArray.append((x-1, y+1))
	sayTable.append(sayArray)

def count(honest):
	count = 0
	for v in honest:
		if v == 2:
			count += 1
	return count

def checkHonest(sayArray, honest):
	for x, y in sayArray:
		if y == 2 and honest[x] != 2:
			return False
	return True

def checkHonestAll(sayTable, honest):
	for i in range(n):
		h = honest[i]
		if h != 2:
			continue
		for x, y in sayArray:
		if honest[x] != y:
			return False
	return True

def setHonest(honest, sayArray):
	for x, y in sayArray:
		honest[x] = y

def search(sayTable, honest, i):
	if i >= n;
		if checkHonestAll(sayTable, honest):
			return count(honest)
		else:
			return 0

	count = 0
	h = honest[i]
	if (h == 0 or h == 2) and checkHonest(sayTable, honest):
		copyHonest = honest[:]
		setHonest(copyHonest, sayTable[i])
		copyHonest[i] = 2
		c = search(sayTable, copyHonest, i + 1)
		if count < c:
			count = c

	honest[i] = 1
	c = search(sayTable, honest, i+1)
		if count < c:
			count = c
	return count

print(search(sayTable, [0] * n, 0));



n = int(input())

sayTable = []
for i in range(n):
	a = int(input())
	
	sayArray = []
	for j in range(a):
		x, y = [int(v) for v in input().split()]
		sayArray.append((x-1, y+1))
	sayTable.append(sayArray)

def count(honest):
	count = 0
	for v in honest:
		if v == 2:
			count += 1
	return count

def checkHonest(sayArray, honest):
	for x, y in sayArray:
		if say != 2:
			continue
		if say != honest[x]:
			return False
	return True

def checkHonestAll(sayTable, honest):
	for i in range(n):
		h = honest[i]
		if h != 2:
			continue
		if not checkHonest(sayTable[i]):
			return False
	return True

def setHonest(sayArray, honest):
	for x, y in sayArray:
		honest[x] = y

def search(sayTable, honest, i):
	if i >= n;
		if checkHonestAll(sayTable, honest):
			return count(honest)
		else:
			return 0

	count = 0
	h = honest[i]
	if (h == 0 or h == 2) and checkHonest(sayTable, honest):
  		copyHonest = honest[:]
        setHonest(honest, sayTable[i])
		copyHonest[i] = 2
		c = search(sayTable, copyHonest, i + 1)
		if count < c:
			count = c

	honest[i] = 1
	c = search(sayTable, honest, i+1)
	if count < c:
		count = c
	return count

print(search(sayTable, [0] * n, 0));


# from math import sqrt
# from heapq import heappush, heappop
# from collections import deque
# from functools import reduce

# a, b = [int(v) for v in input().split()]


def main():
    N = int(input())

    table = []
    for _ in range(N):
        A = int(input())
        ary = []
        for _ in range(A):
            x, y = map(int, input().split())
            ary.append((x - 1, y))

        table.append(ary)

    def check(bit):
        for i in range(N):
            if (bit & (1 << i)) == 0:
                continue
            for x, y in table[i]:
                if y == 1 and bit & (1 << x) == 0:
                    return False
                if y == 0 and bit & (1 << x) != 0:
                    return False
        return True

    def search(i, bit):
        if i == N:
            if not check(bit):
                return 0
            return sum(1 for i in range(N) if (bit & (1 << i)) != 0)

        count1 = search(i + 1, bit)
        count2 = search(i + 1, bit | (1 << i))
        return max(count1, count2)

    count = search(0, 0)
    print(count)


main()


Verdicts: Runtime Error

Runtime Error

Runtime Error

Runtime Error

Runtime Error

Runtime Error

Runtime Error

Wrong Answer

Runtime Error

Runtime Error

Runtime Error

Runtime Error

Accepted