poj2182(单点更新)

len[rt]表示当前树中有多少个空位;还有就是在网右子树走的时候一定要减掉左子树的空位数目。

/*****************************************
Author      :Crazy_AC(JamesQi)
Time        :2015
File Name   :
*****************************************/
// #pragma comment(linker, "/STACK:1024000000,1024000000")
#include <iostream>
#include <algorithm>
#include <iomanip>
#include <sstream>
#include <string>
#include <stack>
#include <queue>
#include <deque>
#include <vector>
#include <map>
#include <set>
#include <stdio.h>
#include <string.h>
#include <math.h>
#include <stdlib.h>
#include <limits.h>
using namespace std;
#define MEM(a,b) memset(a,b,sizeof a)
typedef long long LL;
typedef unsigned long long ULL;
typedef pair<int,int> ii;
const int inf = 1 << 30;
const int INF = 0x3f3f3f3f;
const int MOD = 1e9 + 7;
inline int Readint(){
	char c = getchar();
	while(!isdigit(c)) c = getchar();
	int x = 0;
	while(isdigit(c)){
		x = x * 10 + c - '0';
		c = getchar();
	}
	return x;
}
const int maxn = 8010;
int len[maxn << 2];
int num[maxn],ans[maxn],pos,n;
void Build(int L,int R,int rt){
	len[rt] = R - L + 1;
	if (L == R) return ;
	int mid = (L + R) >> 1;
	Build(L,mid,rt << 1);
	Build(mid + 1,R,rt << 1 | 1);
}
void Updata(int L,int R,int rt,int p){
	len[rt]--;
	if (L == R){
		pos = L;
		return ;
	}
	int mid = (L + R) >> 1;
	if (p <= len[rt << 1]) Updata(L,mid,rt << 1,p);
	else Updata(mid + 1,R,rt << 1 | 1,p - len[rt << 1]);
	return ;
}
int main()
{	
	// freopen("in.txt","r",stdin);
	// freopen("out.txt","w",stdout);
	while(~scanf("%d",&n)){
		num[1] = 0;
		for (int i = 2;i <= n;i++)
			num[i] = Readint();
		Build(1,n,1);
		for (int i = n;i >= 1;i--){
			Updata(1,n,1,num[i] + 1);
			ans[i] = pos;
		}
		for (int i = 1;i <= n;i++)
			printf("%d\n",ans[i]);
	}
	return 0;
}


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