Exemple #1
0
	void sol(){

		if(s2<s1){
			vi t=a;a=b;b=t;
			ll x=s1;s1=s2;s2=x;
			t=ida;ida=idb;idb=t;
			fliped=!fliped;
		}

		if(a.empty() || b.empty())return ;

		if(abs(s1-s2)==0){return ;}

		ll diff = abs(s2 - s1);
		ll Y = diff;
		int x,y;
		x=y=0;
	//	printf("diff = %lld\n",diff);

		for (int i = 0; i < a.size(); ++i) {

			vi::iterator it = lower_bound(b.begin(), b.end(), diff/2 + a[i]);
			int j = it-b.begin();
			if(j && j == b.size())j--;

//			printf("i,j=%d,%d\n",i,j);

			ll ns1 = s1 - a[i] + b[j];
			ll ns2 = s2 - b[j] + a[i];

	//		printf("debug a[%d] = %d b[%d] = %d\n",i,a[i],j,b[j]);
	//		printf("debug ns1 = %lld ns2 = %lld\n",ns1,ns2);
			if(abs(ns1 - ns2) < Y){
				x = i;
				y = j;
	//			printf("debug %d %d\n",x,y);
				Y = abs(ns1 - ns2);
			}
		}



		if(Y<diff){
//			printf("swaping a[%d] b[%d] diff = %lld\n", x,y, Y);
			if(fliped)
				ans.push_back(ii(idb[y],ida[x]));
			else
				ans.push_back(ii(ida[x],idb[y]));
			s1 = s1 - a[x] + b[y];
			s2 = s2 + a[x] - b[y];
		}

//		printf("x,y = %d %d\n",x,y);

		a.erase(move(a,x));
		ida.erase(move(ida,x));
		b.erase(move(b,y));
		idb.erase(move(idb,y));
	}
Exemple #2
0
  bool query(const vvpi& T, const vi& Qin)
  {
    if ( Qin.empty() ) return true;
    if ( Qin.size() == 1 ) return !T[ Qin[0] ].empty();
    auto Q = Qin; // copy the query
    sort(Q.begin(), Q.end());

    for ( auto p : T[ Q[0] ] )
    {
      int i, k; tie(i, k) = p;
      int s = 1;

      while ( k <= Q[s] && k > -1 )
      {
        s += k == Q[s];
        if ( s == Q.size() )
          return true;

        auto it = lower_bound( T[k].begin(), T[k].end(), i,
            [](const pi& x, int val) -> bool { return x.first < val; } );
        if (it == T[k].end() || it->first != i)
          break;

        k = it->second;
      }
    }

    return false;
  }
Exemple #3
0
  bool query(const vvi& T, const vi& Q)
  {
    if ( Q.empty() ) return true;
    vi S = T[ Q[0] ];
    if ( Q.size() == 1 ) return !S.empty();

    for ( int i = 1; i < Q.size(); ++i )
    {
      const auto& TQi = T[ Q[i] ];
      workspace_vec.clear();
      set_intersection( S.begin(), S.end(), TQi.begin(), TQi.end(),
          back_inserter(workspace_vec));
      S = workspace_vec;
      if ( S.empty() )
        return false;
    }
    return !S.empty();
  }
Exemple #4
0
void out(vi & a)
{
	printf("%d", a.empty() ? 0 : a.back());
	for (int i = int(a.size()) - 2; i >= 0; i--)
		printf("%09d", a[i]);
}
int main() {
#ifdef DEBUG
  time_t startt = clock();
#endif
  isprime.set();
  isprime[0] = isprime[1] = 0;
  for(int i = 0; i<20015; i++)
  if(isprime[i]) {
    for(int j = i*i; j<20015; j+= i)
      isprime[j] = 0;
  }
  scanf("%d", &n);
  p.assign(n+2, 0);
  q.assign(n+2, 0);
  int cnt[] = {0, 0};
  s = n; t = n+1;
  memset(res, 0, sizeof res);
  for(int i = 0; i<n; i++) {
    scanf("%d", a+i);
    if(a[i] & 1) {
      cnt[0]++;
      res[s][i] = 2;
    }
    else {
      res[i][t] = 2;
      cnt[1]++;
    }
  }
  if(cnt[0] != cnt[1]) {
    puts("Impossible");
    return 0;
  }
  for(int i = 1; i<n; i++)
    for(int j = 0; j<i; j++)
      if(isprime[a[i]+a[j]]) {
        if(a[i] & 1)
          res[i][j] = 1; 
        else
          res[j][i] = 1;
      }
  int flow = 0;
  n += 2;
  while(1) {
    f = 0;
    vis.reset();
    queue< int > q;
    p.assign(n, -1);
    q.push(s);
    vis[s] = 1;
    while(!q.empty()) {
      int u = q.front(); q.pop();
      if(u == t) break;
      for(int i = 0; i<n; i++)
        if(!vis[i] && res[u][i] > 0)
          p[i] = u, vis[i] = 1, q.push(i);
    }
    augment(t, 1000000);
    if(f == 0) break;
    flow += f;
  }
  if(flow != (cnt[0]<<1)) {
    puts("Impossible");
    return 0;
  }
  vis.set();
  n -= 2;
  for(int i = 0; i<n; i++) if(vis[i] && (a[i] & 1)) {
    int v = i;
    ans.push_back(vi());
    while(vis[v]) {
      ans.back().push_back(v);
      vis[v] = 0;
      for(int j = 0; j<n; j++) {
        if(vis[j] && ((a[j] & 1) == 0) && res[j][v]) {
          v = j;
          break;
        }
      }
      ans.back().push_back(v);
      vis[v] = 0;
      for(int j = 0; j<n; j++)
        if(vis[j] && (a[j] & 1) && res[v][j]) {
          v = j;
          break;
        }
    }
  }
  printf("%d\n", ans.size());
  for(int i = 0; i<ans.size(); i++) {
    printf("%d", ans[i].size());
    for(int j = 0; j< ans[i].size(); j++)
      printf(" %d", ans[i][j] + 1);
    printf("\n");
  }
#ifdef DEBUG
  cerr << "Running time  : " << (double)(clock()-startt) * 1000 / CLOCKS_PER_SEC << " ms" << endl;
  int T = time(NULL)-1491365861;
  cerr << "Time  : " << T/60 << " minutes " << T%60 << " secs" << endl;
#endif
  return 0;
}