ZOJ 3299-Fall the Brick（线段树+离散化）

#include <map>
#include <set>
#include <list>
#include <cmath>
#include <queue>
#include <stack>
#include <cstdio>
#include <vector>
#include <string>
#include <cctype>
#include <complex>
#include <cassert>
#include <utility>
#include <cstring>
#include <cstdlib>
#include <iostream>
#include <algorithm>
using namespace std;
typedef pair<int,int> PII;
typedef long long ll;
#define lson l,m,rt<<1
#define pi acos(-1.0)
#define rson m+1,r,rt<<1|1
#define All 1,N,1
#define N 100010
#define read freopen("in.txt", "r", stdin)
const ll  INFll = 0x3f3f3f3f3f3f3f3fLL;
const int INF= 0x7ffffff;
const int mod =  1000000007;
int res[4*N],f[1<<20],x,y;
ll sum[1<<20],tmp[N],add[1<<20];
struct brick{
    int l,r,lid,rid;
}a[N];
struct board{
    int l,r,lid,rid,h,id;
}b[N];
bool cmp(board u,board v){
    return u.h>v.h;
}
void pushup(int rt){
    sum[rt]=sum[rt<<1]+sum[rt<<1|1];
}
void pushdown(int rt,int l,int r){
    int mid=(l+r)>>1;
    if(add[rt]){
       add[rt<<1]+=add[rt];
       add[rt<<1|1]+=add[rt];
       sum[rt<<1]+=1LL*(res[mid+1]-res[l])*add[rt];
       sum[rt<<1|1]+=1LL*(res[r+1]-res[mid+1])*add[rt];
       add[rt]=0;
    }
}
void build(int l,int r,int rt){
    sum[rt]=add[rt]=f[rt]=0;
    if(l==r)return;
    int m=(l+r)>>1;
    build(lson);
    build(rson);
}
void update_add(int L,int R,int v,int l,int r,int rt){
    if(L<=l&&R>=r){
       add[rt]+=v;
        sum[rt]+=(res[r+1]-res[l])*v;
        return;
    }
    pushdown(rt,l,r);
    int m=(l+r)>>1;
    if(L<=m)update_add(L,R,v,lson);
    if(R>m)update_add(L,R,v,rson);
    pushup(rt);
}
void update_cle(int L,int R,int l,int r,int rt){
    if(f[rt])return;
    if(L<=l&&R>=r){
        sum[rt]=0;
        f[rt]=1;
        return;
    }
    pushdown(rt,l,r);
    int m=(l+r)>>1;
    if(L<=m)update_cle(L,R,lson);
    if(R>m)update_cle(L,R,rson);
    pushup(rt);
}
ll query(int L,int R,int l,int r,int rt){
        if(f[rt])return 0;
        if(L<=l&&R>=r){
            return sum[rt];
        }
        pushdown(rt,l,r);
        ll num=0;
       int  m=(l+r)>>1;
        if(L<=m)num+=query(L,R,lson);
        if(R>m)num+=query(L,R,rson);
        return num;
}
int main()
{
    while(~scanf("%d%d",&x,&y)){
            int len=0;
        for(int i=0;i<x;++i){
            scanf("%d%d",&a[i].l,&a[i].r);
            res[len++]=a[i].l;
            res[len++]=a[i].r;
        }
        for(int i=0;i<y;++i){
            scanf("%d%d%d",&b[i].l,&b[i].r,&b[i].h);
            res[len++]=b[i].l;
            res[len++]=b[i].r;
            b[i].id=i;
        }
        //离散化
        sort(res,res+len);
        len=unique(res,res+len)-res;
        for(int i=0;i<x;++i){
            a[i].lid=lower_bound(res,res+len,a[i].l)-res;
            a[i].rid=lower_bound(res,res+len,a[i].r)-res;
        }
        for(int i=0;i<y;++i){
            b[i].lid=lower_bound(res,res+len,b[i].l)-res;
            b[i].rid=lower_bound(res,res+len,b[i].r)-res;
        }
        build(0,len-1,1);
        for(int i=0;i<x;++i)
            update_add(a[i].lid,a[i].rid-1,1,0,len-1,1);//左开右闭
             sort(b,b+y,cmp);
            for(int i=0;i<y;++i){
                tmp[b[i].id]=query(b[i].lid,b[i].rid-1,0,len-1,1);
                update_cle(b[i].lid,b[i].rid-1,0,len-1,1);
            }
        for(int i=0;i<y;++i){
            printf("%I64d\n",tmp[i]);
        }
        printf("\n");
    }
return 0;
}