Hdu2871Memory Control线段树

#include <cstdio>
#include <cstring>
#include <algorithm>
#include <climits>
#include <string>
#include <iostream>
#include <map>
#include <cstdlib>
#include <list>
#include <set>
#include <queue>
#include <stack>
#include<math.h>
#include<vector>
using namespace std;
#define lson l,mid,rt<<1
#define rson mid+1,r,rt<<1|1
const int maxn = 55555;
int color[maxn << 2], sum[maxn << 2], lsum[maxn << 2], rsum[maxn << 2];
struct Node
{
    int a; int b;
};
int a;
vector<Node > q;
void down(int rt, int m)
{
    if (~color[rt]){
        color[rt << 1] = color[rt << 1 | 1] = color[rt];
        sum[rt << 1] = lsum[rt << 1] = rsum[rt << 1] = color[rt] ? 0 : (m - (m >> 1));
        sum[rt << 1 | 1] = lsum[rt << 1 | 1] = rsum[rt << 1 | 1] = color[rt] ? 0 : (m >> 1);
        color[rt] = -1;
    }
}

void up(int rt, int m)
{
    lsum[rt] = lsum[rt << 1];
    rsum[rt] = rsum[rt << 1 | 1];
    if (lsum[rt] == (m - (m >> 1))) lsum[rt] += lsum[rt << 1 | 1];
    if (rsum[rt] == (m >> 1)) rsum[rt] += rsum[rt << 1];
    sum[rt] = max(max(sum[rt << 1], sum[rt << 1 | 1]), rsum[rt << 1] + lsum[rt << 1 | 1]);
}

void build(int l, int r, int rt)
{
    color[rt] = -1;sum[rt]=lsum[rt]=rsum[rt]=r-l+1;
    if(l==r) return ;
    int mid = (l + r) >> 1;
    build(lson);
    build(rson);
}

void update(int L, int R, int add, int l, int r, int rt)
{
    if (L <= l&&r <= R){
        sum[rt] = lsum[rt] = rsum[rt] = add ? 0 : (r - l + 1);
        color[rt] = add;
        return;
    }
    down(rt, r - l + 1);
    int mid = (l + r) >> 1;
    if (L <= mid) update(L, R, add, lson);
    if (R > mid)  update(L, R, add, rson);
    up(rt, r - l + 1);
}

int ask(int key, int l, int r, int rt)
{
    if (l == r) return l;
    down(rt, r - l + 1);
    int mid = (l + r) >> 1;
    if (key <= sum[rt << 1]) return ask(key, lson);
    if (rsum[rt << 1] + lsum[rt << 1 | 1] >= key) return mid - rsum[rt << 1] + 1;
    return ask(key, rson);
}
int erfen(int x)
{
    int l = 0; int r = q.size() - 1;
    while (l <= r){
        int mid = (l + r) >> 1;
        if (q[mid].a > x){
            r = mid - 1;
        }
        else l = mid + 1;
    }
    return l;
}
int  main()
{
    int n, m;
    char str[100];
    while (scanf("%d%d",&n,&m)!=EOF){
        build(1, n, 1);
        q.clear();
        for (int i = 0; i < m; i++){
            scanf("%s", str);
            if (str[0] == ‘R‘){
                update(1,n,0,1,n,1);
                q.clear();printf("Reset Now\n");continue;
            }
            scanf("%d", &a);
            if (str[0] == ‘N‘){
                if(sum[1]<a){
                    printf("Reject New\n");continue;
                }
                int t = ask(a, 1, n, 1);
                int pos = erfen(t);
                Node gg; gg.a = t; gg.b = t + a - 1;
                q.insert(q.begin() + pos, gg);
                update(t, t + a - 1, 1, 1, n, 1);
                printf("New at %d\n", t);
            }
            if (str[0] == ‘F‘){
                int pos = erfen(a)-1;
                if (pos<=-1||q[pos].b < a){
                    printf("Reject Free\n"); continue;
                }
                update(q[pos].a, q[pos].b, 0, 1, n, 1);
                printf("Free from %d to %d\n", q[pos].a, q[pos].b);
                q.erase(q.begin()+pos,q.begin()+pos+1);
            }
            if (str[0] == ‘G‘){
                if (q.size() < a){
                    printf("Reject Get\n"); continue;
                }
                printf("Get at %d\n", q[a-1].a);
            }
        }
        printf("\n");
    }
    return 0;
}