BZOJ 1015: [JSOI2008]星球大战starwar

二次联通门 : BZOJ 1015: [JSOI2008]星球大战starwar

/*
    BZOJ 1015: [JSOI2008]星球大战starwar

    离线删点
    先建出删完点后的图
    然后一个一个往上加删掉的点
*/
#include <cstdio>
#include <iostream>
#define Max 400004
#define rg register
struct E { E *n; int v; } *list[Max], poor[Max], *Ta = poor;
int f[Max], C, p[Max], s[Max]; bool is[Max];
inline void read (int &n)
{
    rg char c = getchar ();
    for (n = 0; !isdigit (c); c = getchar ());
    for (; isdigit (c); n = n * 10 + c - '0', c = getchar ()); ++ n;
}
inline int Find (int x) { return f[x] == x ? x : f[x] = Find (f[x]); }
int main (int argc, char *argv[])
{
    int N, M, n, x, y, V, K; read (N), read (M); rg int i, j; -- N, -- M; E *e;
    for (i = 0; i < M; ++ i)
    {
        read (x), read (y);
        ++ Ta, Ta->n = list[x], list[x] = Ta, Ta->v = y;
        ++ Ta, Ta->n = list[y], list[y] = Ta, Ta->v = x;
    }
    read (K); -- K; C = N - K; for (i = 1; i <= N; f[i] = i, ++ i);
    for (i = 1; i <= K; ++ i) read (p[i]), is[p[i]] = true; 
    for (i = 1; i <= N; ++ i)
    {
        if (is[i]) continue;
        for (e = list[i]; e; e = e->n)
            if (!is[(V = e->v)])
            {
                x = Find (i), y = Find (V);
                if (x != y) f[x] = y, -- C;
            }
    }
    for (i = K, s[K + 1] = C; i >= 1; -- i)
    {
        n = p[i], is[n] = false; ++ C;
        for (e = list[n]; e; e = e->n)
            if (!is[(V = e->v)])
            {
                x = Find (n), y = Find (V);
                if (x != y) f[x] = y, -- C;
            }
        s[i] = C;
    }
    for (i = 1; i <= K + 1; ++ i) printf ("%d
", s[i]); return 0;
}