We have a permutation of the integers from 1 through N, p_1, p_2, .., p_N.
We also have M pairs of two integers between 1 and N (inclusive), represented as (x_1,y_1), (x_2,y_2), .., (x_M,y_M).
AtCoDeer the deer is going to perform the following operation on p as many times as desired so that the number of i (1 ≤ i ≤ N) such that p_i = i is maximized:
 - Choose j such that 1 ≤ j ≤ M, and swap p_{x_j} and p_{y_j}.
Find the maximum possible number of i such that p_i = i after operations.
-----Constraints-----
 - 2 ≤ N ≤ 10^5
 - 1 ≤ M ≤ 10^5
 - p is a permutation of integers from 1 through N.
 - 1 ≤ x_j,y_j ≤ N
 - x_j ≠ y_j
 - If i ≠ j, \{x_i,y_i\} ≠ \{x_j,y_j\}.
 - All values in input are integers.
-----Input-----
Input is given from Standard Input in the following format:
N M
p_1 p_2 .. p_N
x_1 y_1
x_2 y_2
:
x_M y_M
-----Output-----
Print the maximum possible number of i such that p_i = i after operations.
-----Sample Input-----
5 2
5 3 1 4 2
1 3
5 4
-----Sample Output-----
2
If we perform the operation by choosing j=1, p becomes 1 3 5 4 2, which is optimal, so the answer is 2.
from collections import deque

n, m = map(int, input().split())
plst = list(map(int, input().split()))
edges = [[] for _ in range(n)]
for _ in range(m):
    x, y = map(int, input().split())
    x -= 1
    y -= 1
    edges[x].append(y)
    edges[y].append(x)
    
check = [False for _ in range(n)]
uni = [0 for _ in range(n)]
pos = 0
queue = deque()
for i in range(n):
    if check[i]:
        continue
    pos += 1
    queue.append(i)
    check[i] = True
    while queue:
        now = queue.popleft()
        uni[now] += pos
        uni[plst[now] - 1] -= pos
        for aft in edges[now]:
            if check[aft]:
                continue
            check[aft] = True
            queue.append(aft)
print(uni.count(0))
from collections import deque

n, m = map(int, input().split())
plst = list(map(int, input().split()))
edges = [[] for _ in range(n)]
for _ in range(m):
    x, y = map(int, input().split())
    x -= 1
    y -= 1
    edges[x].append(y)
    edges[y].append(x)
    
check = [False for _ in range(n)]
uni = [0 for _ in range(n)]
pos = 0
queue = deque()
for i in range(n):
    if check[i]:
        continue
    pos += 1
    queue.append(i)
    check[i] = True
    while queue:
        now = queue.popleft()
        uni[now] += pos
        uni[plst[now] - 1] -= pos
        for aft in edges[now]:
            if check[aft]:
                continue
            check[aft] = True
            queue.append(aft)
print(uni.count(0))