| # | Time | Username | Problem | Language | Result | Execution time | Memory |
|---|---|---|---|---|---|---|---|
| 866611 | fanwen | Alternating Heights (CCO22_day1problem1) | C++17 | 0 ms | 0 KiB |
This submission is migrated from previous version of oj.uz, which used different machine for grading. This submission may have different result if resubmitted.
/**
* author : pham van sam
* created : 26.10.2023 20:29:38
**/
#include <bits/stdc++.h>
using namespace std;
#define MASK(x) (1LL << (x))
#define BIT(x, i) (((x) >> (i)) & 1)
#define ALL(x) (x).begin(), (x).end()
#define REP(i, n) for (int i = 0, _n = n; i < _n; ++i)
#define FOR(i, a, b) for (int i = (a), _b = (b); i <= _b; ++i)
#define FORD(i, a, b) for (int i = (a), _b = (b); i >= _b; --i)
#define FORE(i, a, b) for (int i = (a), _b = (b); i < _b; ++i)
#define debug(...) "[" << #__VA_ARGS__ ": " << (__VA_ARGS__) << "] "
#define file(name) if (fopen(name".inp", "r")) { freopen(name".inp", "r", stdin); freopen(name".out", "w", stdout); }
template <class A, class B> bool minimize(A &a, B b) { if (a > b) { a = b; return true; } return false; }
template <class A, class B> bool maximize(A &a, B b) { if (a < b) { a = b; return true; } return false; }
const int MAXN = 3e3 + 5;
int N, K, Q, A[MAXN], res[MAXN], deg_in[MAXN], visit[MAXN], exist[MAXN];
vector <int> adj[MAXN];
void dfs(int u, int &ok) {
visit[u] = 1;
for (auto v : adj[u]) if(visit[v] < 2) {
if(visit[v] == 1) {
ok = 0;
return;
} else {
dfs(v, ok);
}
}
visit[u] = 2;
}
bool not_cycles(int l, int r) {
fill(adj + 1, adj + K + 1, vector <int>());
fill(deg_in + 1, deg_in + K + 1, 0);
fill(visit + 1, visit + K + 1, 0);
fill(exist + 1, exist + K + 1, 0);
FOR(i, l, r) {
exist[A[i]] = 1;
if(i & 1) {
if(i + 1 <= r) {
adj[A[i]].push_back(A[i + 1]);
deg_in[A[i + 1]]++;
}
if(i - 1 >= l) {
adj[A[i]].push_back(A[i - 1]);
deg_in[A[i - 1]]++;
}
}
// if(l == 2 && r == 4) {
// if(i % 2 == 1 && i + 1 <= r) {
// cout << A[i] << " " << A[i + 1] << '\n';
// }
// if(i % 2 == 0 && i - 1 >= l) {
// cout << A[i] << " " << A[i - 1] << '\n';
// }
// }
}
FOR(i, 1, K) if(exist[i] && !deg_in[i]) {
int oke = true;
dfs(i, oke);
if(!oke) return false;
}
FOR(i, 1, K) if(exist[i] && !visit[i]) return false;
return true;
}
void you_make_it(void) {
cin >> N >> K >> Q;
FOR(i, 1, N) cin >> A[i];
int j = 1;
FOR(i, 1, N) {
while(j <= N && not_cycles(i, j)) ++j;
res[i] = j;
// cout << res[i] << " \n"[i == N];
}
while(Q--) {
int l, r; cin >> l >> r;
cout << (res[l] <= r ? "NO\n" : "YES\n");
}
}
signed main() {
#ifdef LOCAL
freopen("TASK.inp", "r", stdin);
freopen("TASK.out", "w", stdout);
#endif
auto start_time = chrono::steady_clock::now();
cin.tie(0), cout.tie(0) -> sync_with_stdio(0);
you_make_it();
auto end_time = chrono::steady_clock::now();
cerr << "\nExecution time : " << chrono::duration_cast <chrono::milliseconds> (end_time - start_time).count() << "[ms]" << endl;
return (0 ^ 0);
}
// Dream it. Wish it. Do it.