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IDProblemSubmitterResultTimeMemoryLanguageFile sizeSubmit timeJudge time
#397392#6638. TreelectionUSP_USP_USP#WA 127ms32688kbC++141.9kb2024-04-24 01:13:222024-04-24 01:13:22

Judging History

你现在查看的是最新测评结果

  • [2024-04-24 01:13:22]
  • 评测
  • 测评结果:WA
  • 用时:127ms
  • 内存:32688kb
  • [2024-04-24 01:13:22]
  • 提交

answer

#include <bits/stdc++.h>
using namespace std;
#define pb push_back
#define mp make_pair
#define fi first
#define se second
#define int long long
void dbg_out() { cerr << endl; }
template <typename H, typename... T>
void dbg_out(H h, T... t) { cerr << ' ' << h; dbg_out(t...); }
#define dbg(...) { cerr << #__VA_ARGS__ << ':'; dbg_out(__VA_ARGS__); }
using ll = long long;
mt19937_64 rng(chrono::steady_clock::now().time_since_epoch().count());

const int MAXN = 1e6+5;
const int MOD = 1e9+7; //998244353;
const int INF = 0x3f3f3f3f;
const ll INF64 = ll(4e18) + 5;

vector<int> g[MAXN];
int sz[MAXN];


void dfs(int u, int p){
	sz[u] = 1;
	for(auto v : g[u]) if(v != p){
		dfs(v,u);
		sz[u] += sz[v];
	}
}

int rec(int u, int x, int lim){
	if(lim < 0){
		return INF;
	}
	if(u == x) return 1;
	int sum = 0;
	for(auto v : g[u]){
		sum += rec(v,x,lim);
	}
	sum -= lim;
	sum = max(sum,0ll);
	sum += 1;
	return sum;
}

void solve(){
	int n;
	cin >> n;
	for(int i = 0; i < n; i++){
		g[i].clear();
	}
	for(int i = 1; i < n; i++){
		int p;
		cin >> p;
		p--;
		g[p].pb(i);
	}
	dfs(0,0);
	vector<pair<int,int>> vs(n);
	for(int i = 0; i <n; i++){
		vs[i]= { sz[i],i};
	}
	sort(vs.begin(),vs.end());
	int l = 0;
	int r = n-1;
	string ans(n,'0');
	while(l < r){
		int mid = (l+r)/2;
		//I cannot have more than vs[mid].fi-2 since mid will get vs[mid].fi - 1
		int ret = rec(0,vs[mid].se, vs[mid].fi-2);
		if(ret == 1){
			r = mid;
		}else{
			l = mid+1;
		}
	}
	for(int i = l; i < n; i++){
		int id = vs[i].se;
		ans[id] = '1';
	}
	cout << ans << '\n';
}

signed main(){

    ios::sync_with_stdio(false); cin.tie(NULL);

    int t = 1;
    cin >> t;
    while(t--){
        solve();
    }

    return 0;
}

/*
Makefile:
CXXFLAGS=-Wall -Wextra -Wshadow -g -pedantic -fsanitize=address,undefined -D_GLIBCXX_DEBUG -D_GLIBCXX_DEBUGPEDANTIC -std=gnu++17
*/

Details

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Test #1:

score: 100
Accepted
time: 0ms
memory: 27580kb

input:

2
4
1 2 3
5
1 1 2 2

output:

1100
10000

result:

ok 2 lines

Test #2:

score: -100
Wrong Answer
time: 127ms
memory: 32688kb

input:

10
100000
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 10...

output:

111111111111111111111111111111111111111111111111111111111111111111111111111111111111111111111111111111111111111111111111111111111111111111111111111111111111111111111111111111111111111111111111111111111111111111111111111111111111111111111111111111111111111111111111111111111111111111111111111111111111...

result:

wrong answer 1st lines differ - expected: '111111111111111111111111111111...0000000000000000000000000000000', found: '111111111111111111111111111111...0000000000000000000000000000000'