Submission #1096355

#	Time	Username	Problem	Language	Result	Execution time	Memory
1096355		ducdev	Global Warming (CEOI18_glo)	C++14	38 / 100	61 ms	7192 KiB

glo

// Author: 4uckd3v - Nguyen Cao Duc
#include <bits/stdc++.h>
using namespace std;
 
#define all(x) (x).begin(), (x).end()
 
typedef long long ll;
 
const int MAX_N = 1e6;
const int MOD = 1e9 + 7;
 
int n;
ll a[MAX_N + 5], x;
 
struct FenwickTree {
    vector<int> bit;
    int n;
 
    void update(int pos, int val) {
        for (; pos <= n; pos += pos & (-pos))
            bit[pos] = max(bit[pos], val);
    };
 
    int get(int pos) {
        int ret = 0;
        for (; pos > 0; pos -= pos & (-pos))
            ret = max(ret, bit[pos]);
        return ret;
    };
 
    FenwickTree(int n) : n(n) {
        bit.assign(n + 5, 0);
    };
};
 
namespace SUBTASK_1 {
    const int N = MAX_N;
 
    int dp[N + 5][5];
 
    void Solve() {
        int res = 0;
        for (int i = 1; i <= n; i++) {
            for (int j = 0; j < 4; j++) dp[i][j] = 1;
            for (int j = 1; j < i; j++) {
                if (a[i] + x > a[j]) {
                    dp[i][1] = max(dp[i][1], dp[j][0] + 1);
                };
                if (a[i] - x > a[j]) {
                    dp[i][2] = max(dp[i][2], dp[j][0] + 1);
                };
                if (a[i] > a[j]) {
                    dp[i][0] = max(dp[i][0], dp[j][0] + 1);
                    dp[i][1] = max(dp[i][1], dp[j][1] + 1);
                    dp[i][2] = max(dp[i][2], dp[j][2] + 1);
                };
                if (a[i] > a[j] + x) {
                    dp[i][3] = max(dp[i][3], dp[j][1] + 1);
                };
                if (a[i] > a[j] - x) {
                    dp[i][4] = max(dp[i][4], dp[j][2] + 1);
                };
            }
            res = max({res, dp[i][0], dp[i][1], dp[i][2], dp[i][3], dp[i][4]});
        }
 
        cout << res << '\n';
    };
};  // namespace SUBTASK_1
 
namespace SUBTASK_2 {
    const int N = MAX_N;
 
    ll c[N + 5];
 
    void Solve() {
        vector<ll> v;
        for (int i = 1; i <= n; i++) c[i] = a[i];
        for (int i = 1; i <= n; i++) v.push_back(c[i]);
 
        sort(all(v));
        v.resize(unique(all(v)) - v.begin());
 
        for (int i = 1; i <= n; i++) {
            c[i] = lower_bound(all(v), c[i]) - v.begin() + 1;
        };
 
        FenwickTree bit(n);
        int res = 0;
        for (int i = 1; i <= n; i++) {
            int dp = bit.get(c[i] - 1);
            bit.update(c[i], dp + 1);
            res = max(res, dp + 1);
        }
 
        cout << res << '\n';
    };
};  // namespace SUBTASK_2
 
int main() {
    ios_base::sync_with_stdio(0);
    cin.tie(0);
    if (fopen("MAIN.INP", "r")) {
        freopen("MAIN.INP", "r", stdin);
        freopen("MAIN.OUT", "w", stdout);
    };
 
    cin >> n >> x;
    for (int i = 1; i <= n; i++) {
        cin >> a[i];
    };
 
    if (x == 0)
        return SUBTASK_2::Solve(), 0;
 
if (n <= 1000)   return SUBTASK_1::Solve(), 0;
  cout<< n;
};

Compilation message (stderr)

glo.cpp: In function 'int main()':
glo.cpp:104:16: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
  104 |         freopen("MAIN.INP", "r", stdin);
      |         ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~
glo.cpp:105:16: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
  105 |         freopen("MAIN.OUT", "w", stdout);
      |         ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~

• Subtask 1: 5 / 5
• Subtask 2: 10 / 10
• Subtask 3: 13 / 13
• Subtask 4: 10 / 10
• Subtask 5: 0 / 20
• Subtask 6: 0 / 17
• Subtask 7: 0 / 25