Submission #14696

#	Time	Username	Problem	Language	Result	Execution time	Memory
14696		minsu	Tropical Garden (IOI11_garden)	C++14	100 / 100	2313 ms	15644 KiB

garden

#include <cstdio>
#include <cstring>
#include <cstdlib>
#include <queue>
#include "garden.h"
#include "gardenlib.h"
using namespace std;
const int MAXN=1e6;
int elast[MAXN], eprev[MAXN], eadj[MAXN], eind;
int bpath[MAXN][2], bpathn[MAXN];
int L[MAXN], C[MAXN];
void add_edge(int u, int v){
  eadj[eind]=v; eprev[eind]=elast[u]; elast[u]=eind++;
}
void count_routes(int N, int M, int P, int R[][2], int Q, int G[])
{
  for(int i=0;i<M;i++){
    int u=R[i][0], v=R[i][1];
    if(bpathn[u]<2) bpath[u][bpathn[u]++]=v;
    if(bpathn[v]<2) bpath[v][bpathn[v]++]=u;
  }
  for(int i=0;i<N;i++) if(bpathn[i]==1) bpath[i][1]=bpath[i][0], bpathn[i]++;
  memset( elast, -1, sizeof elast );
  // Vertex 0 to 2*N-1
  for(int u=0;u<N;u++){
  	if(bpathn[u]==0) continue;
    int F=bpath[u][0], S=bpath[u][1];
    if(bpath[F][0]!=u) add_edge(F*2, u*2); else add_edge(F*2+1, u*2);
    if(bpath[S][0]!=u) add_edge(S*2, u*2+1); else add_edge(S*2+1, u*2+1);
  }
  memset( C, -1, sizeof C );
  queue<int> q; q.push(P*2); q.push(P*2+1);
  L[P*2]=L[P*2+1]=0; C[P*2]=P*2; C[P*2+1]=P*2+1;
  while(!q.empty()){
  	int here=q.front(); q.pop();
  	for(int i=elast[here];i!=-1;i=eprev[i]){
  		int there=eadj[i];
  		L[there]=L[here]+1; C[there]=C[here];
  		if(there/2==P) continue;
  		q.push(there);
  	}
  }
  for(int i=0;i<Q;i++){
    int ans=0;
    for(int b=0;b<2*N;b+=2){
        int g=G[i], bb=b;
        if(C[bb]==-1) continue;
        g-=L[bb]; bb=C[bb];
        if(g>0){ g-=L[bb]; bb=C[bb]; }
        if(g>0){
            if(bb==C[bb] && L[bb]!=0){
                g%=L[bb];
            }else if(bb!=C[bb] && L[bb]!=0 && L[C[bb]]!=0){
                g%=(L[bb]+L[C[bb]]);
            }
        }
        while(g>0 && bb!=-1 && L[bb]!=0){
            g-=L[bb]; bb=C[bb];
        }
        if(g==0) ans++;
    }
    answer(ans);
  }
}

• Subtask 1: 49 / 49
• Subtask 2: 20 / 20
• Subtask 3: 31 / 31