oj.uz

Submission #139045

# Submission time Handle Problem Language Result Execution time Memory
139045 2019-07-31T08:33:59 Z MAMBA Highway Tolls (IOI18_highway) C++17
51 / 100
 279 ms 9336 KB 
#include "highway.h"
#include <bits/stdc++.h>

using namespace std;

#define rep(i , j , k) for(int i = j; i < (int)k; i++)
#define all(x) x.begin(),x.end()
#define pb push_back

inline bool smin(int &a , int b) { return b < a ? a = b , true : false; }

typedef vector<int> vi;
typedef long long ll;

void find_pair(int N,  vi U, vi V, int A, int B) {
	int M = U.size();

	vector<vi> adj(N);
	rep(i , 0 , M) {
		adj[U[i]].pb(i);
		adj[V[i]].pb(i);
	}

	// faze 1 : peyda kardan fasele 
	int len = ask(vi(M)) / A;

	auto cnt = [&](vi cond) ->int {
		ll res = ask(cond);
		return (res - 1ll * A * len) / (B - A);
	};




	// faze 2 : peyda kardane ye yal to masir

	int lovelyEdge = -1;

	{
		int lo = -1 , hi = M - 1;
		while (lo != hi - 1) {
			int mid = lo + hi >> 1;
			vi local(mid + 1 , 1);
			local.resize(M);


			if (ask(local) != 1ll * A * len)
				hi = mid;
			else 
				lo = mid;
		}
		lovelyEdge = hi;
	}

	// faze 3 : peyda kardane rasaye chap va rasaye rast va sakhtane deralht chap o rast :

	vector<bool> active(N , true);
	vi d1(N) , d2(N);
	vi edge1, edge2;
	auto bfs = [&](int v , vi &d, vi& edge) {

		edge.clear();
		fill(all(d) , 1e9);
		vi q(N);
		int L = 0 , R = 0;

		assert(active[v]);
		d[v] = 0;
		q[R++] = v;
		while (L < R) {
			v = q[L++];		
			for (auto e : adj[v]) {
				int u = V[e] ^ U[e] ^ v;
				if (!active[u]) continue;
				if (smin(d[u] , d[v] + 1)) {
					q[R++] = u;
					if (V[e] == u) swap(U[e] , V[e]);
					edge.pb(e);
				}
			}
		}
		return;
	};

	int V1 = V[lovelyEdge];
	int V2 = U[lovelyEdge];

	bfs(V1 , d1 , edge1);
	bfs(V2 , d2 , edge2);




	fill(all(active) , false);
	rep(i , 0 , N) if (d1[i] < d2[i]) active[i] = true;
	bfs(V1 , d1 , edge1);

	fill(all(active) , false);
	rep(i , 0 , N) if (d2[i] < d1[i]) active[i] = true;
	bfs(V2 , d2 , edge2);


	// faze 4 : [eyd akardan s O t:

	auto finder = [&](int root , vi & edge) {
		int len2 = -1;
		{
			vi local(M);
			for (auto e : edge)
				local[e] = 1;
			len2 = cnt(local);
		}

		if (!len2) return root;

		int lo = -1 , hi = edge.size() - 1;
		while (lo != hi - 1) {
			int mid = lo + hi >> 1;

			vi local(M);
			rep(i , 0 , mid + 1)
				local[edge[i]] = true;

			if (cnt(local) == len2) hi = mid;
			else lo = mid;
		}
		return U[edge[hi]];
	};

	int S = finder(U[lovelyEdge] , edge1);
	int T = finder(V[lovelyEdge] , edge2);

	answer(S , T);

	return;


}

Compilation message

highway.cpp: In function 'void find_pair(int, vi, vi, int, int)':
highway.cpp:42:17: warning: suggest parentheses around '+' inside '>>' [-Wparentheses]
    int mid = lo + hi >> 1;
              ~~~^~~~
highway.cpp: In lambda function:
highway.cpp:118:17: warning: suggest parentheses around '+' inside '>>' [-Wparentheses]
    int mid = lo + hi >> 1;
              ~~~^~~~

Subtask #1
5.0 / 5.0

# Verdict Execution time Memory Grader output
1 Correct 2 ms 376 KB Output is correct
2 Correct 2 ms 376 KB Output is correct
3 Correct 2 ms 376 KB Output is correct
4 Correct 2 ms 376 KB Output is correct
5 Correct 2 ms 248 KB Output is correct
6 Correct 2 ms 324 KB Output is correct
7 Correct 2 ms 376 KB Output is correct
8 Correct 2 ms 248 KB Output is correct
9 Correct 2 ms 248 KB Output is correct
10 Correct 2 ms 316 KB Output is correct
11 Correct 2 ms 248 KB Output is correct
12 Correct 2 ms 248 KB Output is correct

Subtask #2
7.0 / 7.0

# Verdict Execution time Memory Grader output
1 Correct 3 ms 376 KB Output is correct
2 Correct 24 ms 1320 KB Output is correct
3 Correct 231 ms 8980 KB Output is correct
4 Correct 249 ms 8972 KB Output is correct
5 Correct 276 ms 8996 KB Output is correct
6 Correct 231 ms 9008 KB Output is correct
7 Correct 258 ms 9004 KB Output is correct
8 Correct 241 ms 8996 KB Output is correct
9 Correct 211 ms 9008 KB Output is correct
10 Correct 250 ms 8996 KB Output is correct
11 Correct 252 ms 8904 KB Output is correct
12 Correct 247 ms 8908 KB Output is correct
13 Correct 259 ms 8912 KB Output is correct
14 Correct 264 ms 8908 KB Output is correct

Subtask #3
6.0 / 6.0

# Verdict Execution time Memory Grader output
1 Correct 16 ms 1252 KB Output is correct
2 Correct 42 ms 2356 KB Output is correct
3 Correct 72 ms 3328 KB Output is correct
4 Correct 163 ms 8900 KB Output is correct
5 Correct 164 ms 8936 KB Output is correct
6 Correct 179 ms 8900 KB Output is correct
7 Correct 158 ms 9004 KB Output is correct
8 Correct 191 ms 8948 KB Output is correct
9 Correct 161 ms 8980 KB Output is correct

Subtask #4
33.0 / 33.0

# Verdict Execution time Memory Grader output
1 Correct 3 ms 484 KB Output is correct
2 Correct 24 ms 1264 KB Output is correct
3 Correct 128 ms 7176 KB Output is correct
4 Correct 258 ms 9000 KB Output is correct
5 Correct 242 ms 8988 KB Output is correct
6 Correct 220 ms 8948 KB Output is correct
7 Correct 203 ms 9004 KB Output is correct
8 Correct 229 ms 8992 KB Output is correct
9 Correct 236 ms 9016 KB Output is correct
10 Correct 233 ms 9008 KB Output is correct
11 Correct 270 ms 8908 KB Output is correct
12 Correct 274 ms 8896 KB Output is correct
13 Correct 260 ms 8952 KB Output is correct
14 Correct 264 ms 8896 KB Output is correct
15 Correct 239 ms 8996 KB Output is correct
16 Correct 226 ms 9008 KB Output is correct
17 Correct 256 ms 8908 KB Output is correct
18 Correct 279 ms 8924 KB Output is correct
19 Correct 225 ms 8968 KB Output is correct
20 Correct 244 ms 8908 KB Output is correct
21 Correct 199 ms 9304 KB Output is correct
22 Correct 161 ms 9336 KB Output is correct
23 Correct 198 ms 9276 KB Output is correct
24 Correct 227 ms 9228 KB Output is correct
25 Correct 262 ms 8952 KB Output is correct

Subtask #5
0 / 18.0

# Verdict Execution time Memory Grader output
1 Incorrect 27 ms 1292 KB Output is incorrect: {s, t} is wrong.
2 Halted 0 ms 0 KB -

Subtask #6
0 / 31.0

# Verdict Execution time Memory Grader output
1 Incorrect 28 ms 1328 KB Output is incorrect: {s, t} is wrong.
2 Halted 0 ms 0 KB -