【BestCoder】 HDOJ 5021 Revenge of kNN II

一个二分里套一个二分就行了。。。。

#include <iostream>  
#include <queue>  
#include <stack>  
#include <map>  
#include <set>  
#include <bitset>  
#include <cstdio>  
#include <algorithm>  
#include <cstring>  
#include <climits>
#include <cstdlib>
#include <cmath>
#include <time.h>
#define maxn 100005
#define maxm 300005
#define eps 1e-10
#define mod 10000007
#define INF 2e9
#define lowbit(x) (x&(-x))
#define mp make_pair
#define ls o<<1
#define rs o<<1 | 1
#define lson o<<1, L, mid  
#define rson o<<1 | 1, mid+1, R  
//typedef long long LL;
typedef int LL;
using namespace std;
LL qpow(LL a, LL b){LL res=1,base=a;while(b){if(b%2)res=res*base;base=base*base;b/=2;}return res;}
LL powmod(LL a, LL b){LL res=1,base=a;while(b){if(b%2)res=res*base%mod;base=base*base%mod;b/=2;}return res;}
void scanf(int &__x){__x=0;char __ch=getchar();while(__ch==' '||__ch=='\n')__ch=getchar();while(__ch>='0'&&__ch<='9')__x=__x*10+__ch-'0',__ch = getchar();}
LL gcd(LL _a, LL _b){if(!_b) return _a;else return gcd(_b, _a%_b);}
// head

struct point
{
	int x, id;
	double v;
}p[maxn];
double tree[maxn<<2];
int n, m, ql, qr, pp;
int mpp[maxn];
double v;

int cmp(point a, point b)
{
	return a.x < b.x;
}
void read(void)
{
	scanf("%d%d", &n, &m);
	for(int i = 1; i <= n; i++) scanf("%d%lf", &p[i].x, &p[i].v), p[i].id = i;
	sort(p+1, p+n+1, cmp);
	p[0].x = -INF, p[n+1].x = INF, p[n+1].id = INF, p[0].id = INF;
	for(int i = 1; i <= n; i++) mpp[p[i].id] = i;
}
int find1(int now, int k)
{
	int bot = 0, top = n+1, mid, res;
	while(top >= bot) {
		mid = (top + bot) >> 1;
		if(p[mid].x >= k) res = mid, top = mid-1;
		else bot = mid+1;
	}
	return res;
}
int find2(int now, int k)
{
	int bot = 0, top = n+1, mid, res;
	while(top >= bot) {
		mid = (top + bot) >> 1;
		if(p[mid].x > k) top = mid-1;
		else bot = mid+1, res = mid;
	}
	return res;
}
void search(int now, int k)
{
	int bot = 1, top = 1000000000, mid, t1, t2;
	while(top >= bot) {
		mid = (top + bot) >> 1;
		t1 = find1(now, p[now].x - mid);
		t2 = find2(now, p[now].x + mid);
		int t = t2 - t1;
		if(t == k) {
			ql = t1, qr = t2;
			break;
		}
		if(t == k+1 && abs(p[t1].x - p[now].x) == abs(p[t2].x - p[now].x)) {
			if(p[t1].id > p[t2].id) ql = t1+1, qr = t2;
			else ql = t1, qr = t2-1;
			break;
		}
		if(t > k) top = mid-1;
		else bot = mid+1;
	}
}
void pushup(int o)
{
	tree[o] = tree[ls] + tree[rs];
}
void build(int o, int L, int R)
{
	if(L == R) {
		tree[o] = p[L].v;
		return;
	}
	int mid = (L + R) >> 1;
	build(lson);
	build(rson);
	pushup(o);
}
double query(int o, int L, int R)
{
	if(ql <= L && qr >= R) return tree[o];
	int mid = (L + R) >> 1;
	double ans = 0;
	if(ql <= mid) ans += query(lson);
	if(qr > mid) ans += query(rson);
	return ans;
}
void updata(int o, int L, int R)
{
	if(L == R) {
		tree[o] = v;
		return;
	}
	int mid = (L + R) >> 1;
	if(pp <= mid) updata(lson);
	else updata(rson);
	pushup(o);
}
void debug(void)
{
	search(mpp[4], 2);
	printf("AA %d %d BB\n", ql, qr);
}
void work(void)
{
	int id, k;
	double sum, ans = 0;
	build(1, 1, n);
	while(m--) {
		scanf("%d%d", &id, &k);
		id = mpp[id];
		search(id, k);
		sum = query(1, 1, n);
		sum -= p[id].v;
		//printf("BBBBBBB %d %d\n", ql, qr);
		sum /= k;
		//printf("AAAA %f\n", sum);
		ans += sum;
		pp = id, v = sum, p[id].v = v;
		//printf("VCVVVVVVV %f\n", v);
		updata(1, 1, n);
	}
	printf("%.3f\n", ans);
}
int main(void)
{
	int _;
	while(scanf("%d", &_)!=EOF) {
		while(_--) {
			read();
			//debug();
			work();
		}
	}
	return 0;
}