http://acm.pku.edu.cn/JudgeOnline/problem?id=3667 区间更新+求满足长短的最左区间

#include <iostream>#include <cstdio>#include <algorithm>#define LL(x) ((x) << 1)#define RR(x) ((x) << 1 | 1)using namespace std;const int N = 500005;struct Seg_tree {int l, r;int st;int l_size, size, r_size;int mid() {return (l + r) >> 1;}void doit() {l_size = size = r_size = st ? 0 : len();/*if (st == 0)l_size = size = r_size = len();elsel_size = size = r_size = 0;*/}int len() {return (r - l + 1);}} tree[4 * N];inline void Build(int l, int r, int node) {tree[node].l = l;tree[node].r = r;tree[node].st = -1;tree[node].l_size = tree[node].size = tree[node].r_size = tree[node].len();if (l == r) {return;}//int mid = (r + l) >> 1;int mid = tree[node].mid();Build(l, mid, LL(node));Build(mid + 1, r, RR(node));}inline void Update(int l, int r, int node, int st) {if (l <= tree[node].l && tree[node].r <= r) {tree[node].st = st;tree[node].doit();return;}if (tree[node].st != -1) {tree[LL(node)].st = tree[RR(node)].st = tree[node].st;tree[LL(node)].doit();tree[RR(node)].doit();tree[node].st = -1;}int mid = tree[node].mid();if(l <= mid)Update(l, r, LL(node), st);if(mid < r)Update(l, r, RR(node), st);/*if (r <= mid) {Update(l, r, LL(node), st);} else if (l > mid) {Update(l, r, RR(node), st);} else {Update(l, mid, LL(node), st);Update(mid + 1, r, RR(node), 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[node].r_size = tree[RR(node)].r_size;if (tree[LL(node)].size == tree[LL(node)].len()) {tree[node].l_size += tree[RR(node)].l_size;}if (tree[RR(node)].size == tree[RR(node)].len()) {tree[node].r_size += tree[LL(node)].r_size;}}inline int Query(int size, int node) {if (tree[node].l == tree[node].r && size == 1) {return tree[node].l;}if (tree[node].st != -1) {tree[LL(node)].st = tree[RR(node)].st = tree[node].st;tree[LL(node)].doit();tree[RR(node)].doit();tree[node].st = -1;}if (tree[LL(node)].size >= size) {return Query(size, LL(node));} else if (tree[LL(node)].r_size + tree[RR(node)].l_size >= size) {return tree[LL(node)].r - tree[LL(node)].r_size + 1;} else if (tree[RR(node)].size >= size) {return Query(size, RR(node));} else {return 0;}}int main() {int n, m;while (scanf("%d %d", &n, &m) != EOF) {Build(1, n, 1);while (m--) {int ca;scanf("%d", &ca);if (ca == 1) {int a;scanf("%d", &a);int s = Query(a, 1);printf("%d/n", s);if (s) {Update(s, s + a - 1, 1, 1);}} else {int a, b;scanf("%d %d", &a, &b);Update(a, a + b - 1, 1, 0);}}}}