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 
       
         #include 
        
          #include 
         
           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; }