Submission #574356

#	Time	Username	Problem	Language	Result	Execution time	Memory
574356		tamthegod	Global Warming (CEOI18_glo)	C++14	100 / 100	550 ms	47704 KiB

glo

#include<iostream>
#include<iomanip>
#include<algorithm>
#include<stack>
#include<queue>
#include<string>
#include<string.h>
#include<cmath>
#include<vector>
#include<map>
#include<unordered_map>
#include<set>
#include<unordered_set>
#include<cstdio>
#include<bitset>
#include<chrono>
#include<random>
#include<ext/rope>
/* ordered_set
#include<ext/pb_ds/assoc_container.hpp>
#include<ext/pb_ds/tree_policy.hpp>
using namespace __gnu_pbds;
#define ordered_set tree<int, null_type,less<int>, rb_tree_tag,tree_order_statistics_node_update>
*/
#define int long long
#define pb push_back
#define fi first
#define se second
using namespace std;
using ll = long long;
using ld = long double;
using ull = unsigned long long;
mt19937 rng(chrono::steady_clock::now().time_since_epoch().count());
const int maxN = 1e6 + 5;
const int mod = 1e9 + 7;
const ll oo = 1e18;
int n, x, a[maxN];
int b[maxN];
int f[maxN], e[maxN];
int dp[maxN];
int st[4 * maxN];
void update(int id, int l, int r, int pos, int val)
{
    if(l > pos || r < pos) return;
    if(l == r && l == pos)
    {
        st[id] = val;
        return;
    }
    int mid = (l + r) / 2;
    update(id * 2, l, mid, pos, val);
    update(id * 2 + 1, mid + 1, r, pos, val);
    st[id] = min(st[id * 2], st[id * 2 + 1]);
}
int get(int id, int l, int r, int u, int v)
{
    if(l > v || r < u) return oo;
    if(l >= u && r <= v) return st[id];
    int mid = (l + r) / 2;
    return min(get(id * 2, l, mid, u, v), get(id * 2 + 1, mid + 1, r, u, v));
}
void ReadInput()
{
    cin >> n >> x;
    for(int i=1; i<=n; i++) cin >> a[i];
}
void Solve()
{
    for(int i=1; i<=n; i++) b[i] = -a[i];
    memset(e, 3, sizeof e);
    for(int i=n; i>=1; i--)
    {
        int j = lower_bound(e + 1, e + n + 1, b[i]) - e;
        dp[i] = j;
        e[dp[i]] = b[i];
    }
    memset(e, 3, sizeof e);
    for(int i=1; i<=n; i++)
    {
        int j = lower_bound(e + 1, e + n + 1, a[i]) - e;
        f[i] = j;
        e[f[i]] = a[i];
    }
    memset(st, 3, sizeof st);
    int res = 0;
    for(int i=1; i<=n; i++)
    {
        int tmp = a[i] + x - 1;
        int low = 1, high = n, mid;
        while(low <= high)
        {
            mid = (low + high) / 2;
            if(get(1, 1, n, mid, n) <= tmp) low = mid + 1;
            else high = mid - 1;
        }
        res = max(res, dp[i] + high);
        update(1, 1, n, f[i], a[i]);
    }
    cout << res << '\n';
}
int32_t main()
{
    //freopen("x.inp", "r", stdin);
    ios_base::sync_with_stdio(false);
    cin.tie(nullptr);
    ReadInput();
    Solve();
}

• 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