# | 제출 시각 | 아이디 | 문제 | 언어 | 결과 | 실행 시간 | 메모리 |
---|---|---|---|---|---|---|---|
699480 | arcane | Alternating Heights (CCO22_day1problem1) | C++17 | 0 ms | 0 KiB |
이 제출은 이전 버전의 oj.uz에서 채점하였습니다. 현재는 제출 당시와는 다른 서버에서 채점을 하기 때문에, 다시 제출하면 결과가 달라질 수도 있습니다.
#include <bits/stdc++.h>
using namespace std;
#define int long long
#define fi first
#define se second
#define mp make_pair
#define pb emplace_back
const int MAX_N = 5005;
vector <int> edg[MAX_N], topo;
int arr[MAX_N], ans[MAX_N], cur;
bool marked[MAX_N], flag;
int n;
void dfs(int x){
marked[x] = true;
for (auto edge : edg[x]){
if (!marked[edge]) dfs(edge);
}
topo.pb(x);
}
void dfs2(int x){
if (marked[x]) return;
marked[x] = true;
for (auto edge : edg[x]){
if (!marked[edge]) flag = true;
}
}
bool check(int x){
//if (cur == 1) cerr << cur << ' ' << x << '\n';
for (int i = 0; i < k; i++) edg[i].clear();
topo.clear(); fill(marked, marked + k, 0);
for (int i = cur; i < x; i++){
if ((i - cur) % 2) edg[arr[i]].pb(arr[i + 1]);
else edg[arr[i + 1]].pb(arr[i]);
if (arr[i] == arr[i + 1]) return false;
/*if (cur == 1){
if ((i - cur) % 2) cerr << arr[i] << ' ' << arr[i + 1] << '\n';
else cerr << arr[i + 1] << ' ' << arr[i] << '\n';
}*/
}
for (int i = 0; i < n; i++){
if (!marked[i]) dfs(i);
}
//reverse(topo.begin(), topo.end());
//if (cur == 1) for (auto tmp : topo) cerr << tmp << ' ';
//if (cur == 1) cerr << '\n';
fill(marked, marked + k, 0);
flag = false;
for (auto nod : topo){
if (!marked[nod]){
dfs2(nod);
/*if (cur == 1){
cerr << nod << ' ' << flag << '\n';
for (int j = 0; j < 3; j++) cerr << marked[j] << ' ';
cerr << '\n';
}*/
}
}
//if (cur == 1) cerr << '\n';
return !flag;
}
void init(){
for (int i = 0; i < n; i++){
int lo = i, hi = n, mi; cur = i;
/*if (i == 1){
cerr << "Checking 1: \n"; check(4);
cerr << "DONE\n";
}*/
while (lo + 1 != hi){
mi = (lo + hi) / 2;
if (check(mi)) lo = mi;
else hi = mi;
//cerr << i << ' ' << lo << ' ' << hi << '\n';
}
ans[i] = lo;
}
}
int32_t main(){
ios::sync_with_stdio(false);
cin.tie(0); cout.tie(0);
int k, q, x, y; cin >> n >> k >> q;
for (int i = 0; i < n; i++) cin >> arr[i], arr[i] -= 1;
init();
//for (int i = 0; i < n; i++) cerr << "Highest: " << ans[i] << '\n';
for (int i = 0; i < q; i++){
cin >> x >> y;
x -= 1; y -= 1;
if (y <= ans[x]) cout << "YES\n";
else cout << "NO\n";
}
}