Submission #1280779

#	Time	Username	Problem	Language	Result	Execution time	Memory
1280779		vuquangsang	Global Warming (CEOI18_glo)	C++20	100 / 100	43 ms	3580 KiB

glo

#include <bits/stdc++.h>
using namespace std;

#define     el "\n"
#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     pb push_back
#define     fi first
#define     se second
#define     all(x) x.begin(),x.end()
#define     lg(x) __lg(x)
#define     alla(a,n) a+1,a+n+1
#define     ll long long


template <class T> bool maxi(T &x, T y) { if(x < y) { x = y ; return true ;} return false;}
template <class T> bool mini(T &x, T y) { if(x > y) { x = y ; return true ;} return false;}

const int N = 2e5 + 2;
const int INF = 1e9 + 2;

int n, a[N], lim;

void inp()
{
    cin >> n >> lim;
    FOR(i, 1, n) cin >> a[i];
}

/* Try your best
    No regrets */

namespace subtask_3
{
    int temp[N];
    void slv()
    {
        int ans = 0;
        for(int i = 1; i <= n; i++) {
            a[i] -= lim;
            for(int j = 1; j <= n; j++) temp[j] = INF;

            for(int j = 1; j <= n; j++) {
                int pos = lower_bound(temp + 1, temp + n + 1, a[j]) - temp;
                maxi(ans, pos);
                temp[pos] = a[j];
            }
        }
        cout << ans;
    }
}

namespace subtask_4
{

    int temp[N], dp[N];
    void slv()
    {
        FOR(i, 1, n) temp[i] = INF;

        int ans = 0;
        FOR(i, 1, n) {
            int pos = lower_bound(temp + 1, temp + n + 1, a[i]) - temp;
            dp[i] = pos;
            temp[pos] = a[i];
            maxi(ans, pos);
        }
        cout << ans;
    }
}

namespace subtask_7
{

    int Left[N], Right[N];

    int res = 0;
    int temp[N];
    void prepare()
    {
        FOR(i, 1, n) temp[i] = INF;

        int ans = 0;
        for(int i = 1; i <= n; i++) {
            int pos = lower_bound(temp + 1, temp + n + 1, a[i]) - temp;
            temp[pos] = a[i];
            Left[i] = pos;

        }

        FOR(i, 1, n) temp[i] = INF;

        ans = 0;
        for(int i = n; i >= 1; i--) {

            int pos = lower_bound(temp + 1, temp + n + 1, - a[i] + lim) - temp;
            Right[i] = pos;

            pos = lower_bound(temp + 1, temp + n + 1, - a[i]) - temp;
            temp[pos] = - a[i];
        }
    }
    void slv()
    {
        prepare();

        int ans = 0;
        FOR(i, 1, n) {
            maxi(ans, Left[i] + Right[i] - 1);
        }
        cout << ans;
    }
}
/* Code slowly, think carefully */

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

    #define __Azul__ "glo"
    if(fopen(__Azul__".inp", "r")) {
        freopen(__Azul__".inp", "r", stdin);
        freopen(__Azul__".out", "w", stdout);
    }

    bool qs = 0;

    int T = 1;
    if(qs) cin >> T;
    while(T--) {
        inp();
        subtask_7::slv();
//        if(!lim) subtask_4::slv();
//        else if(n <= 1000) subtask_3::slv();
//        else subtask_7::slv();
    }

    cerr << "\nTime" << 0.001 * clock() << "s "; return 0;


}

Compilation message (stderr)

glo.cpp:116:1: warning: ISO C++ forbids declaration of 'main' with no type [-Wreturn-type]
  116 | main()
      | ^~~~
glo.cpp: In function 'int main()':
glo.cpp:122:16: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
  122 |         freopen(__Azul__".inp", "r", stdin);
      |         ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~~~~
glo.cpp:123:16: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
  123 |         freopen(__Azul__".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