Submission #863758

#	Time	Username	Problem	Language	Result	Execution time	Memory
863758		prohacker	Global Warming (CEOI18_glo)	C++14	100 / 100	163 ms	18848 KiB

glo

#include <bits/stdc++.h>
#define ll long long
#define ld long double

using namespace std;

const int N = 2e5+10;
const int INF = INT_MAX;
const int mod = 1e9+7;

ll a[N],n,r[N],bit[4*N];
ll m;
vector<ll> pos = {};
ll b[N],ans,res;

void pre_calc() {
    for(int i = 0 ; i <= n ; i++) {
        pos.push_back(a[i]+1);
        pos.push_back(a[i]);
        pos.push_back(a[i]-m+1);
    }
    sort(pos.begin(),pos.end());
    pos.resize(unique(pos.begin(),pos.end())-pos.begin());
}

ll get_val(ll x) {
    return lower_bound(pos.begin(),pos.end(),x)-pos.begin()+1;
}

void update(ll id, ll val) {
    while(id > 0) {
        bit[id] = max(bit[id],val);
        id -= (id & (-id));
    }
}

ll get(ll id) {
    ll res = 0;
    while(id <= 3*N) {
        res = max(res,bit[id]);
        id += (id & (-id));
    }
    return res;
}

signed main()
{
    if (fopen("GLO.inp", "r")) {
        freopen("GLO.inp", "r", stdin);
        freopen("GLO.out", "w", stdout);
    }
    ios_base::sync_with_stdio(0);
    cin.tie(0);
    cout.tie(0);
    cin >> n >> m;
    for(int i = 1 ; i <= n ; i++) {
        cin >> a[i];
    }
    pre_calc();
    for(int i = n ; i >= 1 ; i--) {
        ll id = get_val(a[i]-m+1);
        r[i] = get(id)+1;
        ll id2 = get_val(a[i]);
        id = get_val(a[i]+1);
        update(id2,get(id)+1);
        ans = max(ans,r[i]);
    }
    for(int i = 1 ; i <= n ; i++) {
        ll id = lower_bound(b+1,b+res+1,a[i])-b;
        b[id] = a[i];
        res = max(res,id);
        ans = max(ans,id+r[i]-1);
        ans = max(ans,res);
    }
    cout << ans;
    return 0;
}

Compilation message (stderr)

glo.cpp: In function 'int main()':
glo.cpp:49:16: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
   49 |         freopen("GLO.inp", "r", stdin);
      |         ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~
glo.cpp:50:16: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
   50 |         freopen("GLO.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