HDU 4325 Flowers （线段树+离散化）

#include <iostream>
#include <algorithm>
#include <cmath>
#include<functional>
#include <cstdio>
#include <cstdlib>
#include <cstring>
#include <string>
#include <vector>
#include <set>
#include <queue>
#include <stack>
#include <climits>//形如INT_MAX一类的
#define MAX 100050
#define INF 0x7FFFFFFF
#define L(x) x<<1
#define R(x) x<<1|1
using namespace std;

inline void RD(int &ret) {
char c;
do {
c = getchar();
} while(c < '0' || c > '9') ;
ret = c - '0';
while((c=getchar()) >= '0' && c <= '9')
ret = ret * 10 + ( c - '0' );
}
void OT(int a) {
if(a >= 10)OT(a / 10);
putchar(a % 10 + '0');
}

int n,m,cnt,size;
int x[MAX * 3],xx[MAX * 3],le[MAX],ri[MAX],qes[MAX];
struct Node {
int l,r,mid;
int add,v;
} tr[MAX * 4];

void up(int x) {
tr[x].v = tr[L(x)].v + tr[R(x)].v;
}

void down(int x) {
if(tr[x].add != 0) {
int l,r;
tr[L(x)].add += tr[x].add;
tr[R(x)].add += tr[x].add;
l = tr[L(x)].l;
r = tr[L(x)].r;
tr[L(x)].v += (r - l + 1) * tr[x].add;
//tr[L(x)].v = (r - l + 1) * tr[L(x)].add;
l = tr[R(x)].l;
r = tr[R(x)].r;
tr[R(x)].v += (r - l + 1) * tr[x].add;
//tr[R(x)].v = (r - l + 1) * tr[R(x)].add;
tr[x].add = 0;
}
}

void build(int l,int r,int x) {
tr[x].l = l;
tr[x].r = r;
tr[x].mid = (l + r) >> 1;
tr[x].v = 0;
tr[x].add = 0;
if(l == r) return ;

build(l,tr[x].mid,L(x));
build(tr[x].mid + 1,r,R(x));
}

void update(int l,int r,int x,int va) {
if(l <= tr[x].l && r >= tr[x].r) {
tr[x].add += va;
tr[x].v += (tr[x].r - tr[x].l + 1) * va;
//tr[x].v = (tr[x].r - tr[x].l + 1) * tr[x].add;
return ;
}
down(x);
int mid = tr[x].mid;
if(r > mid) update(l,r,R(x),va);
if(l <= mid) update(l,r,L(x),va);
up(x);
}

int ans = 0;
void query(int l,int x) {
if(tr[x].l == tr[x].r) {
ans += tr[x].v;
return ;
}
down(x);
int mid = tr[x].mid;
if(l > mid) query(l,R(x));
if(l <= mid) query(l,L(x));
}

int main() {
int T;
cin >> T;
int ca = 1;
while(T--) {
RD(n);
RD(m);
cnt = 0;
for(int i=0; i<n; i++) {
RD(le[i]);
RD(ri[i]);
x[cnt++] = le[i];
x[cnt++] = ri[i];
}
for(int i=0; i<m; i++) {
RD(qes[i]);
x[cnt++] = qes[i];
}
sort(x,x+cnt);
size = unique(x,x+cnt) - x;
build(1,size,1);
for(int i=0; i<n; i++) {
int ll = lower_bound(x,x+size,le[i]) - x + 1;
int rr = lower_bound(x,x+size,ri[i]) - x + 1;
update(ll,rr,1,1);
}
printf("Case #%d:\n",ca++);
for(int i=0; i<m; i++) {
int q = lower_bound(x,x+size,qes[i]) - x + 1;
ans = 0;
query(q,1);
OT(ans);
puts("");
}
}
return 0;
}