3
2 1 1
 6
6 2 6 2 4 2
 2
1 2
 8
2 1 2 2 6 5 6 6
 18
2 3 4 5 2 7 8 9 10 7 11 12 14 15 13 17 18 18
 7
1 2 3 4 5 6 7
 7
4 3 2 6 3 5 2
 7
7 5 3 1 2 1 5
 7
1 6 4 4 5 6 7

1
2 2 1  0
6 2 6 2 4 2  1 
1 1 
 2 
2 2 2 2 6 2 6 6 
 5 
2 3 4 5 11 7 8 9 10 11 11 11 14 15 11 17 18 11 
 6 
1 1 1 1 1 1 1 
 1
4 3 3 6 3 5 2  1
7 5 3 1 3 1 5  4 
1 6 4 1 1 1 1 

# from debug import debug
import sys; input = sys.stdin.readline
n = int(input())
lis = [0, *map(int , input().split())]
roots = set()
cycles = set()
v = [0]*(n+1)
for i in range(1, n+1):
	if v[i] == 0:
		l = 0; node = start = i
		while v[node] != 1:
			v[node] = 1
			node = lis[node]
			l+=1
		if start == node and l == 1:
			roots.add(start)
		elif start == node and l>1:
			cycles.add(start)
		elif lis[node] == node:
			roots.add(node)
ans = 0
if roots:
	base = roots.pop()
	for i in roots: lis[i] = base; ans+=1
	for i in cycles: lis[i] = base; ans+=1
print(ans)
print(*lis[1:])
