uva 1455 - Kingdom(并查集+线段树)

题目链接：uva 1455 - Kingdom

题目大意：平面上又n个城市，初始时城市之间没有任何双向道路相连，要求一次执行指令。
road A B ：在城市A和城市B之间连接一条双向道路
line C：询问一条y=C的水平线上穿过多少州和这些州总共有多少城市。

一个联通分量算一个州，C保证为小数部分为0.5的实数。

解题思路：线段树维护每个位置上州和城市的个数，并查集维护哪些城市属于同一个州，并且要记录这些州上下范围。每次新建一条道路，要相应根据两个州的y坐标范围对线段树进行维护。

#include <cstdio>
#include <cstring>
#include <algorithm>

using namespace std;
const int maxn = 1e6;
const int maxp = 1e5+5;
#define lson(x) ((x)<<1)
#define rson(x) (((x)<<1)+1)

struct Node {
int l, r, nc, nz;
void set (int l, int r, int nc, int nz) {
this->l = l;
this->r = r;
this->nc = nc;
this->nz = nz;
}
}node[maxn * 4 + 5];

struct Segment {
int l, r;
Segment (int l = 0, int r = 0) {
this->l = l;
this->r = r;
}
}s[maxp];

void add_node(int u, int vc, int vz) {
/*
if (node[u].l == node[u].r && node[u].l == 1)
printf("solve before:%d %d %d %d!\n", node[u].nc, node[u].nz, vc, vz);
*/
node[u].nc += vc;
node[u].nz += vz;
}

void pushup(int u) {
node[u].set(node[lson(u)].l, node[rson(u)].r, 0, 0);
}

void pushdown(int u) {
add_node(lson(u), node[u].nc, node[u].nz);
add_node(rson(u), node[u].nc, node[u].nz);
node[u].nc = node[u].nz = 0;
}

void build_segTree (int u, int l, int r) {
if (l == r) {
node[u].set(l, r, 0, 0);
return;
}

int mid = (l + r) / 2;
build_segTree(lson(u), l, mid);
build_segTree(rson(u), mid + 1, r);
pushup(u);
}

void insert_segTree (int u, int l, int r, int vc, int vz) {
if (l <= node[u].l && node[u].r <= r) {
add_node(u, vc, vz);
return;
}

pushdown(u);
int mid = (node[u].l + node[u].r) / 2;
if (l <= mid)
insert_segTree(lson(u), l, r, vc, vz);
if (r > mid)
insert_segTree(rson(u), l, r, vc, vz);
}

Segment query_segTree (int u, int x) {
if (node[u].l == x && node[u].r == x)
return Segment(node[u].nc, node[u].nz);

pushdown(u);
int mid = (node[u].l + node[u].r) / 2;
if (x <= mid)
return query_segTree(lson(u), x);
else
return query_segTree(rson(u), x);
}

int f[maxp], d[maxp];

void init () {
build_segTree (1, 0, maxn);

int n, x, y;
scanf("%d", &n);
for (int i = 0; i < n; i++) {
f[i] = i;
d[i] = 1;
scanf("%d%d", &x, &y);
s[i].l = s[i].r = y;
}
}

void change (int r, int l, int vc, int vz) {
if (r < l)
return;
insert_segTree (1, l, r, vc, vz);
}

int getfar (int x) {
return x == f[x] ? x : f[x] = getfar(f[x]);
}

void link (int u, int v) {
int x = getfar(u);
int y = getfar(v);

if (x == y)
return;

if (s[x].l > s[y].l)
swap(x, y);

//printf("%d %d %d %d!!!\n", s[x].l, s[x].r, s[y].l, s[y].r);

int root = 1048576;

if (s[y].l >= s[x].r) {
change(s[y].l - 1, s[x].r, 0, 1);
change(s[y].r - 1, s[x].r, d[x], 0);
} else if (s[y].r <= s[x].r) {
change(s[y].r - 1, s[y].l, 0, -1);
change(s[x].r - 1, s[y].r, d[y], 0);
} else {
change(s[x].r - 1, s[y].l, 0, -1);
change(s[y].r - 1, s[x].r, d[x], 0);
}
//printf("fuck:%d %d\n", node[root].nc, node[root].nz);
change(s[y].l - 1, s[x].l, d[y], 0);

s[y].l = min(s[x].l, s[y].l);
s[y].r = max(s[x].r, s[y].r);
f[x] = y;
d[y] += d[x];
}

void solve () {
int n, x, y;
double q;
char order[10];

scanf("%d", &n);
for (int i = 0; i < n; i++) {
scanf("%s", order);
if (strcmp(order, "road") == 0) {
scanf("%d%d", &x, &y);
link(x, y);
} else {
scanf("%lf", &q);
Segment ans = query_segTree(1, (int)q);
printf("%d %d\n", ans.r, ans.l);
}
}
}

int main () {
int cas;
scanf("%d", &cas);
while (cas--) {
init();
solve();
}
return 0;
}