oj.uz

Submission #741543

# Submission time Handle Problem Language Result Execution time Memory
741543 2023-05-14T10:13:50 Z myrcella Highway Tolls (IOI18_highway) C++17
5 / 100
 122 ms 7788 KB 
//by szh
#include<bits/stdc++.h>
using namespace std;

#define fi first
#define se second
#define pii pair<int,int>
#define pll pair<long long,long long>
#define pb push_back
#define debug(x) cerr<<#x<<"="<<x<<endl
#define pq priority_queue
#define inf 0x3f
#define rep(i,a,b) for (int i=a;i<(b);i++)
#define MP make_pair
#define SZ(x) (int(x.size()))
#define ll long long
#define mod 1000000007
#define ALL(x) x.begin(),x.end()
void inc(int &a,int b) {a=(a+b)%mod;}
void dec(int &a,int b) {a=(a-b+mod)%mod;}
int lowbit(int x) {return x&(-x);}
ll p0w(ll base,ll p) {ll ret=1;while(p>0){if (p%2ll==1ll) ret=ret*base%mod;base=base*base%mod;p/=2ll;}return ret;}

#include "highway.h"

const int maxn = 9e4+10;

int fa[maxn];
bool mark[maxn];
bool ans[maxn];
vector <int> ww;
vector <pii> edge[maxn];
int dis,dif;
int ret[maxn];

void solve(vector <int> tmp,int cnt) {
	if (SZ(tmp)==1) {
		ans[tmp[0]] = 1;
		return;
	}
	vector <int> left;
	int mid = SZ(tmp)/2;
	rep(i,0,mid) ww[tmp[i]] = 1,left.pb(tmp[i]);
	int diss = ask(ww);
	rep(i,0,mid) ww[tmp[i]] = 0;
	vector <int> right;
	rep(i,mid,SZ(tmp)) right.pb(tmp[i]);
	if (diss>dis) solve(left,(diss-dis)/dif);
	if ((diss-dis)/dif<cnt) solve(right,cnt-(diss-dis)/dif);
}

bool dfs(int u,int lst,int rest) {
	if (rest==0) return true;
	vector <int> tmp;
	fa[u] = lst;
	int cnt = 0;
	for (pii v:edge[u]) {
		if (v.fi==lst) continue;
		tmp.pb(v.se);
		cnt++;
	}
	assert(cnt!=0);
	if (cnt==1) {
		for (pii v:edge[u]) {
			if (v.fi==lst) continue;
			dfs(v.fi,u,rest-1);
			ans[v.se] = 1;
		}
		return true;
	}
	solve(tmp,1);
	for (pii v:edge[u]) 
		if (v.fi!=lst and ans[v.se]==1) return dfs(v.fi,u,rest-1);
}

void find_pair(int N, std::vector<int> U, std::vector<int> V, int A, int B) {
	rep(i,0,N-1) {
		edge[U[i]].pb({V[i],i});
		edge[V[i]].pb({U[i],i});
	}
	rep(i,1,N) ww.pb(0);
  dis = ask(ww);
  dif = B-A;
  dfs(0,-1,dis/A);
  rep(i,0,N-1) if (ans[i]) ret[U[i]]++,ret[V[i]]++;
  int u=-1,v=-1;
  rep(i,0,N) if (ret[i]==1) {
	  if (u==-1) u = i;
	  else v = i;
  }
  answer(u,v);
}

Compilation message

highway.cpp: In function 'bool dfs(int, int, int)':
highway.cpp:54:15: warning: control reaches end of non-void function [-Wreturn-type]
   54 |  vector <int> tmp;
      |               ^~~

Subtask #1
5.0 / 5.0

# Verdict Execution time Memory Grader output
1 Correct 2 ms 2384 KB Output is correct
2 Correct 2 ms 2384 KB Output is correct
3 Correct 2 ms 2384 KB Output is correct
4 Correct 1 ms 2384 KB Output is correct
5 Correct 2 ms 2432 KB Output is correct
6 Correct 2 ms 2384 KB Output is correct
7 Correct 2 ms 2384 KB Output is correct
8 Correct 2 ms 2384 KB Output is correct
9 Correct 2 ms 2384 KB Output is correct
10 Correct 2 ms 2384 KB Output is correct
11 Correct 2 ms 2384 KB Output is correct
12 Correct 2 ms 2384 KB Output is correct

Subtask #2
0 / 7.0

# Verdict Execution time Memory Grader output
1 Correct 2 ms 2384 KB Output is correct
2 Correct 16 ms 3024 KB Output is correct
3 Incorrect 122 ms 7788 KB Output isn't correct
4 Halted 0 ms 0 KB -

Subtask #3
0 / 6.0

# Verdict Execution time Memory Grader output
1 Incorrect 14 ms 2988 KB Output is incorrect: {s, t} is wrong.
2 Halted 0 ms 0 KB -

Subtask #4
0 / 33.0

# Verdict Execution time Memory Grader output
1 Runtime error 4 ms 4816 KB Execution killed with signal 6
2 Halted 0 ms 0 KB -

Subtask #5
0 / 18.0

# Verdict Execution time Memory Grader output
1 Incorrect 18 ms 3020 KB Incorrect
2 Halted 0 ms 0 KB -

Subtask #6
0 / 31.0

# Verdict Execution time Memory Grader output
1 Incorrect 10 ms 3052 KB Incorrect
2 Halted 0 ms 0 KB -