ZOJ 3299 Fall the Brick (线段树)

#include<cstdio>
#include<iostream>
#include<vector>
#include<algorithm>
#include<cstdlib>
#include<map>

#define lson l ,m ,rt<<1
#define rson m+1 ,r ,rt<<1|1
using namespace std;
typedef long long LL;
const int maxn = 100005;

struct Input{
int id,l,r,h;
bool operator < (const Input &z) const{
return h > z.h;
}
}in[maxn];

int n,q,l[maxn],r[maxn];
int mc[maxn<<2],len;
LL ans[maxn];

int get_id(int x){
return lower_bound(mc,mc+len,x) - mc;
}

struct SegTree{
LL sum[1<<20];int c[1<<20];//bool flag[8*maxn];

void push_up(int rt){
sum[rt] = sum[rt<<1] + sum[rt<<1|1];
}
void push_down(int l,int r,int rt){
if(c[rt] == 0) return;
if(l != r){
c[rt<<1] = (c[rt] != -1) ? c[rt<<1] + c[rt] : -1;
c[rt<<1|1] = (c[rt] != -1) ? c[rt<<1|1] + c[rt] : -1;
}
sum[rt] = (c[rt] != -1) ? sum[rt] + (LL)c[rt]*(mc[r+1]-mc[l]) : 0;
c[rt] = 0;
}
void build(int l,int r,int rt){
c[rt] = 0;//flag[rt ] = false;
if(l == r){
sum[rt] = 0;
return;
}
int m = (l + r) >> 1;
build(lson);build(rson);
push_up(rt);
}
void update(int a,int b,int x,int l,int r,int rt){
push_down(l,r,rt);
if(l > b || r < a) return;
if(a <= l && r <= b){
c[rt] = x;
push_down(l,r,rt);
return;
}
int m = (l + r) >> 1;
update(a,b,x,lson);update(a,b,x,rson);
push_up(rt);
}
LL query(int a,int b,int l,int r,int rt){
push_down(l,r,rt);
if(l > b || r < a) return 0;
if(a <= l && r <= b) return sum[rt];
int m = (l + r) >> 1;
return query(a,b,lson) + query(a,b,rson);
}
}sol;

int main(){
while(~scanf("%d%d",&n,&q)){
int i,o;len = 0;
for(i = 0; i < n ; i++){
scanf("%d%d",&l[i],&r[i]);
mc[len++] = l[i];mc[len++] = r[i];
}
for(i = 0; i < q; i++){
scanf("%d%d%d",&in[i].l,&in[i].r,&in[i].h);in[i].id = i;
mc[len++] = in[i].l;mc[len++] = in[i].r;
}
sort(in,in+q);
sort(mc,mc+len);
len = unique(mc,mc+len) - mc;
o = len;
sol.build(0,o-1,1);
for(i = 0;i < n; i++){
l[i] = get_id(l[i]);r[i] = get_id(r[i]);
sol.update(l[i],r[i]-1,1,0,o-1,1);
}
for(i = 0;i < q; i++){
in[i].l = get_id(in[i].l);in[i].r = get_id(in[i].r);
ans[in[i].id] = sol.query(in[i].l,in[i].r-1,0,o-1,1);
sol.update(in[i].l,in[i].r-1,-1,0,o-1,1);
}
for(i = 0; i < q; i++) printf("%lld\n",ans[i]);
putchar('\n');
}
return 0;
}