http://acm.hdu.edu.cn/showproblem.php?pid=1540 更新节点,询问节点所在的位置有多少连续的区间

/* *这个题目跟hotel差不多的，可以说是一样的。好就没有用vector了，陌生了 *更新节点,询问节点所在的位置有多少连续的区间 */#include <iostream>#include <cstdio>#include <cstring>#include <vector>#include <algorithm>#include <stack>#define LL(x) ((x) << 1)#define RR(x) ((x) << 1 | 1)using namespace std;const int N = 50005;struct Seg_tree {int l, r;int r_size, size, l_size;int mid() {return (l + r) >> 1;}int dis() {return (r - l + 1);}void doit(int st) {if (st == 0) // 0表示修复r_size = size = l_size = dis();elser_size = size = l_size = 0;}} tree[N * 4]; //现在觉得开4倍比较保险vector<int> df;inline void Build(int l, int r, int node) {tree[node].l = l;tree[node].r = r;tree[node].l_size = tree[node].size = tree[node].r_size = tree[node].dis();if (l == r) {return;}int mid = (l + r) >> 1;Build(l, mid, LL(node));Build(mid + 1, r, RR(node));}inline void Update(int node, int dx, int st) {if (tree[node].l == tree[node].r) {tree[node].doit(st);return;}int mid = tree[node].mid();if (dx <= mid)Update(LL(node), dx, st);elseUpdate(RR(node), dx, st);tree[node].size = max(tree[LL(node)].r_size + tree[RR(node)].l_size, max(tree[LL(node)].size, tree[RR(node)].size));tree[node].l_size = tree[LL(node)].l_size ;//+ tree[RR(node)].l_size; // 因为@那里的原因自己修改了这个错误，但是一直不对tree[node].r_size = tree[RR(node)].r_size ;//+ tree[LL(node)].r_size; // 手调的时候才会才发现，没有进入R的那句语句，太菜了if (tree[LL(node)].size == tree[LL(node)].dis()) {tree[node].l_size += tree[RR(node)].l_size;}if (tree[RR(node)].size == tree[RR(node)].dis()) {tree[node].r_size += tree[LL(node)].r_size;}if (dx <= mid) {if (dx > tree[LL(node)].r - tree[LL(node)].r_size) {return Query(LL(node), dx) + Query(RR(node), tree[RR(node)].l);} else {return Query(LL(node), dx);}} else {if (dx < tree[RR(node)].l + tree[RR(node)].l_size) {return Query(RR(node), dx) + Query(LL(node), tree[LL(node)].r);} else {return Query(RR(node), dx);}}}inline int Query(int node, int dx) {if (tree[node].l == tree[node].r || tree[node].size == 0 || tree[node].size== tree[node].dis()) {return tree[node].size;}int mid = tree[node].mid();if (dx <= mid) {if (dx > tree[LL(node)].r - tree[LL(node)].r_size) {return Query(LL(node), dx) + Query(RR(node), tree[RR(node)].l);} else {return Query(LL(node), dx);}} else {if (dx <= mid) {if (dx > tree[LL(node)].r - tree[LL(node)].r_size) {return Query(LL(node), dx) + Query(RR(node), tree[RR(node)].l);} else {return Query(LL(node), dx);}} else {if (dx < tree[RR(node)].l + tree[RR(node)].l_size) {return Query(RR(node), dx) + Query(LL(node), tree[LL(node)].r);} else {return Query(RR(node), dx);}}if (dx < tree[RR(node)].l + tree[RR(node)].l_size) {return Query(RR(node), dx) + Query(LL(node), tree[LL(node)].r);} else {return Query(RR(node), dx);}}}int main() {int n, m;while (scanf("%d %d", &n, &m) != EOF) {Build(1, n, 1);char str[2];int a;df.clear();while (m--) {scanf("%s", str);if (str[0] == 'D') {scanf("%d", &a);df.push_back(a);Update(1, a, 1);} else if (str[0] == 'R') {//if (df.empty()) // @这句话不加也是AC的， 搞了半天原来就是这里弄错了，vector为空的时候返回的真的//continue;int b = df.back();df.pop_back();Update(1, b, 0);} else {scanf("%d", &a);int ans = Query(1, a);printf("%d/n", ans);}}}return 0;}