| # | Time | Username | Problem | Language | Result | Execution time | Memory |
|---|---|---|---|---|---|---|---|
| 1286518 | eri16 | Obstacles for a Llama (IOI25_obstacles) | C++20 | 0 ms | 0 KiB |
#include <bits/stdc++.h>
using namespace std;
int arr1[200005];
int arr2[2][200005];
int arr3[3][200005];
int vis3[3][200005]={0};
int vis2[2][200005]={0};
int dx[4]={0,0,-1,1};
int dy[4]={-1,1,0,0};
int kk=0;
void dfs(int i, int j, int col, int n) {
if (i < 0 || i >= 2 || j < 0 || j >= n) return;
if (arr2[i][j]==0) return;
if (vis[i][j]) return;
vis[i][j] = 1;
arr2[i][j] = col;
for (int z = 0; z < 4; z++) {
dfs(i + dx[z], j + dy[z], col, n);
}
}
void initialize(std::vector<int> T, std::vector<int> H){
if (T.size()==1){
kk=1;
for (int i=0; i<H.size(); i++){
arr1[i]=(T[0]>H[i]) ? 1 : 0;
}
int k=0;
for (int i=0; i<H.size(); i++){
if (arr1[i]==1){arr1[i]=k;}
else{
arr1[i]=-1;
if (i>0){
if (arr1[i-1]!=-1){
k++;
}
}
}
}
}
else if (T.size()==3){
kk=3;
for (int j=0; j<3; j++){
for (int i=0; i<H.size(); i++){
arr2[j][i]=(T[j]>H[i]) ? 1 : 0;
}}
int k=1;
vis3[0][H.size()]=1;
vis3[1][H.size()]=1;
vis3[2][H.size()]=1;
for (int i=0; i<3; i++){
for (int j=0; j<H.size(); j++){if (vis3[i][j]==0){dfs3(i,j,k,H.size());k++;}
}}
}
else{
kk=2;
for (int i=0; i<H.size(); i++){
arr2[0][i]=(T[0]>H[i]) ? 1 : 0;
}
for (int i=0; i<H.size(); i++){
arr2[1][i]=(T[T.size()-1]>H[i]) ? 1 : 0;
}
int k=1;
vis2[0][H.size()]=1;
vis2[1][H.size()]=1;
for (int i=0; i<2; i++){
for (int j=0; j<H.size(); j++){if (vis2[i][j]==0){dfs2(i,j,k,H.size());k++;}
}}
}
}
bool can_reach(int L, int R, int S, int D){
if (kk==0){
return true;
}
if (kk==1){
if (arr1[S]==arr1[D] && arr1[S]!=-1){return true;}
}
if (kk==2){
if (arr2[0][S]==arr2[0][D] && arr2[0][S]!=0){return true;}
}
if (kk==3){
if (arr3[0][S]==arr3[0][D] && arr3[0][S]!=0){return true;}
}
return false;
}
