题解：P8041 [COCI 2016/2017 #7] POKLON

#include<bits/stdc++.h>
using namespace std;
namespace fast_IO {
#define FASTIO
#define IOSIZE 100000
	char ibuf[IOSIZE], obuf[IOSIZE];
	char *p1 = ibuf, *p2 = ibuf, *p3 = obuf;
#ifdef ONLINE_JUDGE
#define getchar() ((p1==p2)and(p2=(p1=ibuf)+fread(ibuf,1,IOSIZE,stdin),p1==p2)?(EOF):(*p1++))
#define putchar(x) ((p3==obuf+IOSIZE)&&(fwrite(obuf,p3-obuf,1,stdout),p3=obuf),*p3++=x)
#endif//fread in OJ, stdio in local

#define isdigit(ch) (ch>47&&ch<58)
#define isspace(ch) (ch<33)
	template<typename T> inline T read() {
		T s = 0;
		int w = 1;
		char ch;
		while (ch = getchar(), !isdigit(ch) and (ch != EOF)) if (ch == '-') w = -1;
		if (ch == EOF) return false;
		while (isdigit(ch)) s = s * 10 + ch - 48, ch = getchar();
		return s * w;
	}
	template<typename T> inline bool read(T &s) {
		s = 0;
		int w = 1;
		char ch;
		while (ch = getchar(), !isdigit(ch) and (ch != EOF)) if (ch == '-') w = -1;
		if (ch == EOF) return false;
		while (isdigit(ch)) s = s * 10 + ch - 48, ch = getchar();
		return s *= w, true;
	}
	inline bool read(char &s) {
		while (s = getchar(), isspace(s));
		return true;
	}
	inline bool read(char *s) {
		char ch;
		while (ch = getchar(), isspace(ch));
		if (ch == EOF) return false;
		while (!isspace(ch)) *s++ = ch, ch = getchar();
		*s = '\000';
		return true;
	}
	template<typename T> inline void print(T x) {
		if (x < 0) putchar('-'), x = -x;
		if (x > 9) print(x / 10);
		putchar(x % 10 + 48);
	}
	inline void print(char x) {
		putchar(x);
	}
	inline void print(char *x) {
		while (*x) putchar(*x++);
	}
	inline void print(const char *x) {
		for (int i = 0; x[i]; ++i) putchar(x[i]);
	}
	inline bool read(std::string& s) {
		s = "";
		char ch;
		while (ch = getchar(), isspace(ch));
		if (ch == EOF) return false;
		while (!isspace(ch)) s += ch, ch = getchar();
		return true;
	}
	inline void print(std::string x) {
		for (int i = 0, n = x.size(); i < n; ++i)
			putchar(x[i]);
	}
	template<typename T, typename... T1> inline int read(T& a, T1&... other) {
		return read(a) + read(other...);
	}
	template<typename T, typename... T1> inline void print(T a, T1... other) {
		print(a);
		print(other...);
	}

	struct Fast_IO {
		~Fast_IO() {
			fwrite(obuf, p3 - obuf, 1, stdout);
		}
	} io;
	template<typename T> Fast_IO& operator >> (Fast_IO &io, T &b) {
		return read(b), io;
	}
	template<typename T> Fast_IO& operator << (Fast_IO &io, T b) {
		return print(b), io;
	}
#define cout io
#define cin io
#define endl '\n'
}
using namespace fast_IO;
const int N = 1e6+5;
struct node
{
	int l;
	int r;
}a[N];
int pre[N];
int v[N];
double dfs(int x)
{
	double l,r;
	if(a[x].l>0)
	{
		l = dfs(a[x].l);
	}
	else 
	{
		l = log2(-a[x].l);
	}
	if(a[x].r>0)
	{
		r = dfs(a[x].r);
	}
	else
	{
		r = log2(-a[x].r);
	}
	if(l>r)
	{
		pre[x] = a[x].l;
	}
	else
	{
		pre[x] = a[x].r;
	}
	return max(l,r)+1;
}
signed main()
{
	int n;
	cin >> n;
	for(int i = 1;i<=n;++i)
	{
		cin >> a[i].l >> a[i].r;
		if(a[i].l>0)
		{
			v[a[i].l] = 1;
		}
		if(a[i].r>0)
		{
			v[a[i].r] = 1;
		}
	}
	for(int i = 1;i<=n;++i)
	{
		if(!v[i])
		{
			dfs(i);
			int x = i,cnt = 0;
			while(x>0)
			{
				x = pre[x];
				++cnt;
			}
			x = -x;
			int flag = 0;
			for(int i = 30;i>=0;--i)
			{
				if(x&(1<<i))
				{
					cout << 1;
					flag = 1;
				}
				else if(flag)
				{
					cout << 0;
				}
			}
			for(int i = 1;i<=cnt;++i)
			{
				cout << 0;
			}
		}
	}
	return 0;
}