Submission #779736

#	Time	Username	Problem	Language	Result	Execution time	Memory
779736		I_Love_EliskaM_	Simurgh (IOI17_simurgh)	C++14	0 / 100	28 ms	308 KiB

simurgh

#include "simurgh.h"
#include <bits/stdc++.h>
using namespace std;
#define forn(i,n) for(int i=0;i<n;++i)
#define pb push_back
#define pi pair<int,int>
#define f first
#define s second
mt19937 rng(chrono::steady_clock::now().time_since_epoch().count());
int rand(int a, int b) {return a+rng()%(b-a+1);}
#define all(x) x.begin(),x.end()


struct DSU {
	vector<int> p,sz;
	DSU(int n) {
		forn(i,n) p.pb(i), sz.pb(1);
	}
	int get(int u) {
		return p[u]==u?u:get(p[u]);
	}
	void uni(int u, int v) {
		u=get(u), v=get(v);
		if (u==v) return;
		if (sz[u]<sz[v]) swap(u,v);
		p[v]=u;
		sz[u]+=sz[v];
	}
};

vector<int> f(vector<int>&z) {
	vector<int> v;
	forn(i,z.size()) if (z[i]) v.pb(i);
	return v;
}
int ask(vector<int>&z) {
	auto v=f(z);
	return count_common_roads(v);
}

vector<int> find_roads(int n, vector<int>u, vector<int>v) {
	int m=u.size();
	if (m==n-1) {
		vector<int> v; forn(i,n) v.pb(i);
		return v;
	}
	if (n>7) exit(0);
	int l=1;
	forn(j,n) l*=m-j;
	forn(mask,1<<m) {
		if (__builtin_popcount(mask)!=n-1) continue;
		vector<int> z(m,0);
		forn(i,m) if ((mask>>i)&1) z[i]=1;
		DSU dsu(n);
		forn(i,m) if (z[i]) dsu.uni(u[i],v[i]);
		if (dsu.sz[dsu.get(0)]!=n) continue;
		int x=ask(z);
		if (x==n-1) return f(z);
		next_permutation(all(z));
	}
}

Compilation message (stderr)

simurgh.cpp: In function 'std::vector<int> first(std::vector<int>&)':
simurgh.cpp:4:32: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
    4 | #define forn(i,n) for(int i=0;i<n;++i)
......
   33 |  forn(i,z.size()) if (z[i]) v.pb(i);
      |       ~~~~~~~~~~                
simurgh.cpp:33:2: note: in expansion of macro 'forn'
   33 |  forn(i,z.size()) if (z[i]) v.pb(i);
      |  ^~~~
simurgh.cpp: In function 'std::vector<int> find_roads(int, std::vector<int>, std::vector<int>)':
simurgh.cpp:61:1: warning: control reaches end of non-void function [-Wreturn-type]
   61 | }
      | ^

• Subtask 1: 0 / 13
• Subtask 2: 0 / 17
• Subtask 3: 0 / 21
• Subtask 4: 0 / 19
• Subtask 5: 0 / 30