Submission #1051442

#	Time	Username	Problem	Language	Result	Execution time	Memory
1051442		manhlinh1501	Global Warming (CEOI18_glo)	C++17	100 / 100	97 ms	17396 KiB

glo

#include <bits/stdc++.h>
using namespace std;
using i64 = long long;
const int MAXN = 1e6 + 5;
#define ALL(a) (a).begin(), (a).end()
#define LB(a, x) (lower_bound(ALL(a), x) - (a).begin() + 1)

struct fenwick0 {
    int tree[MAXN];

    void update(int x, int v) {
        for(; x < MAXN; x += (x & -x))
            tree[x] = max(tree[x], v);
    }

    int get(int x) {
        int res = 0;
        for(; x; x -= (x & -x))
            res = max(res, tree[x]);
        return res;
    }
} bit0;

struct fenwick1 {
    int tree[MAXN];

    void update(int x, int v) {
        for(; x; x -= (x & -x))
            tree[x] = max(tree[x], v);
    }

    int get(int x) {
        int res = 0;
        for(; x < MAXN; x += (x & -x))
            res = max(res, tree[x]);
        return res;
    }
} bit1;

int N, K;
int a[MAXN];
int b[MAXN];
int dp[MAXN];

void compress() {
    vector<int> temp;
    for(int i = 1; i <= N; i++) {
        temp.emplace_back(a[i]);
        temp.emplace_back(b[i]);
    }
    sort(ALL(temp));
    temp.resize(unique(ALL(temp)) - temp.begin());
    for(int i = 1; i <= N; i++) {
        a[i] = LB(temp, a[i]);
        b[i] = LB(temp, b[i]);
    }
}

signed main() {
#define TASK "code"

    if (fopen(TASK ".inp", "r")) {
        freopen(TASK ".inp", "r", stdin);
        freopen(TASK ".out", "w", stdout);
    }

    ios_base::sync_with_stdio(0);
    cin.tie(0);
    cout.tie(0);

    cin >> N >> K;
    for(int i = 1; i <= N; i++) cin >> a[i];
    for(int i = 1; i <= N; i++) b[i] = a[i] + K;
    compress();
    for(int i = 1; i <= N; i++) {
        dp[i] = bit0.get(a[i] - 1) + 1;
        bit0.update(a[i], dp[i]);
    }
    int ans = dp[N];
    for(int i = N; i >= 1; i--) {
        ans = max(ans, dp[i] + bit1.get(a[i] + 1));
        int cur = bit1.get(b[i] + 1);
        bit1.update(b[i], cur + 1);
    }
    cout << ans;
    return (0 ^ 0);
}

Compilation message (stderr)

glo.cpp: In function 'int main()':
glo.cpp:63:16: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
   63 |         freopen(TASK ".inp", "r", stdin);
      |         ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~
glo.cpp:64:16: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
   64 |         freopen(TASK ".out", "w", stdout);
      |         ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~~

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