qwq

#include <stdio.h>
#include <string.h>

#ifdef ONLINE_JUDGE
#define debug(...) 0
#else
#define debug(...) printf(__VA_ARGS__)
#endif

const int SIZE = 4e5 + 5, EDGE = 2e5 + 5;
int n, m, k, u, v;
int father[SIZE]; int cur_blocks;
int target[SIZE], blocks[SIZE];
bool present[SIZE];

int get_ancestor(int node)
{
    while (node != father[node])
        node = father[node] = father[father[node]];
    return node;
}

void merge(int a, int b)
{
    a = get_ancestor(a);
    b = get_ancestor(b);
    if (a != b)
        cur_blocks--;
    father[a] = b;
    return;
}

struct edge
{
    int u, v, next;
}
e[EDGE];
int head[SIZE];
int cnt = 0;

void add_edge(int u, int v)
{
    e[cnt].u = u, e[cnt].v = v, e[cnt].next = head[u];
    head[u] = cnt;
    cnt++;
}

inline void output_dsu()
{
    debug("output_dsu() called\n");
    for (int i = 0; i < n; i++)
        if (father[i] == i && present[i])
            debug("ancestor: %d\n", i);
    debug("blocks: %d\n", cur_blocks);
}

int main()
{
    scanf("%d %d", &n, &m);
    memset(head, -1, sizeof head);
    for (int i = 0; i < m; i++)
        scanf("%d %d", &u, &v), add_edge(u, v), add_edge(v, u);
    memset(present, 1, sizeof present);
    scanf("%d", &k);
    for (int i = 0; i < k; i++)
        scanf("%d", &target[i]), present[target[i]] = 0;

    debug("read done\n");
    debug("e[] dump: \n");
    for (int i = 0; i < cnt; i++)
        debug("e[%d]: u = %d, v = %d, next = %d\n", i, e[i].u, e[i].v, e[i].next);

    for (int i = 0; i < n; i++)
        father[i] = i;
    blocks[k] = cur_blocks = n - k;

    debug("init done\n");
    
    for (int i = 0; i < m; i++)
        if (present[e[i].u] && present[e[i].v])
            merge(e[i].u, e[i].v);
    
    debug("merge done\n");
    output_dsu();
    
    for (int i = k - 1; i >= 0; i--)
    {
        debug("i = %d\n", i);
        cur_blocks++;
        for (int j = head[target[i]]; ~j; j = e[j].next)
            if (present[e[j].v])
                merge(target[i], e[j].v), debug("j = %d\n", j);
        blocks[i] = cur_blocks;
        output_dsu();
    }
    for (int i = 0; i <= k; i++)
        printf("%d\n", blocks[i]);
    return 0;
}
``