Submission #532269

#	Time	Username	Problem	Language	Result	Execution time	Memory
532269		HaYoungJoon	Global Warming (CEOI18_glo)	C++14	0 / 100	216 ms	7712 KiB

glo

#include <bits/stdc++.h>
#define INF 1e9 + 7

using namespace std;

typedef pair<int,int> pii;
int n, X, a[200001], b[200001], res1[200001], res2[200001], L[200001];
map<int,int> mp;
int t[600001], posinIT[200001];

void update(int v, int tl, int tr, int pos, int val) {
    if (tl == tr) {
        t[v] = val;
        return;
    }
    int tm = (tl + tr)/2;
    if (pos <= tm) update(2*v,tl,tm,pos,val);
    else update(2*v+1,tm+1,tr,pos,val);
    t[v] = max(t[2*v],t[2*v+1]);
}

int getMax(int v, int tl, int tr, int l, int r) {
    if (l > r) return -INF;
    if (tl > r || tr < l) return -INF;
    if (tl >= l && tr <= r) return t[v];
    int tm = (tl + tr)/2;
    return max(getMax(2*v,tl,tm,l,r),getMax(2*v+1,tm+1,tr,l,r));
}

int main()
{
    ios_base::sync_with_stdio(0); cin.tie(0);
    cin >> n >> X;
    vector<pii> tmp;
    for (int i = 1; i <= n; i++) {
        cin >> a[i];
        tmp.push_back(pii(a[i],i));
    }
    sort(tmp.begin(),tmp.end());
    int cnt = 1;
    for (int i = 0; i < tmp.size(); i++) posinIT[tmp[i].second] = i+1;
    int lis = 0;
    for (int i = n; i >= 1; i--) {
        int pos = upper_bound(L,L + lis, -a[i]) - L;
        L[pos] = -a[i];
        res1[i] = pos + 1;
        update(1,1,n,posinIT[i],res1[i]);
        lis = max(lis, pos + 1);
    }
    for (int i = 1; i <= n; i++) a[i] -= X;
    lis = 0;
    for (int i = 1; i <= n; i++) {
        int pos = upper_bound(L,L + lis, a[i]) - L;
        L[pos] = a[i];
        res2[i] = pos + 1;
        lis = max(lis, pos + 1);
    }
    int res = res2[n];
    for (int i = 1; i <= n; i++) {
        pii A = pii(a[i],INF);
        update(1,1,n,posinIT[i], -INF);
        int l = upper_bound(tmp.begin(),tmp.end(),A) - tmp.begin() + 1;
        int cur = max(0,getMax(1,1,n, l, n));
        res = max(res,res2[i] + cur);
    }
    cout << res;
    return 0;
}

Compilation message (stderr)

glo.cpp: In function 'int main()':
glo.cpp:41:23: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<std::pair<int, int> >::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   41 |     for (int i = 0; i < tmp.size(); i++) posinIT[tmp[i].second] = i+1;
      |                     ~~^~~~~~~~~~~~
glo.cpp:40:9: warning: unused variable 'cnt' [-Wunused-variable]
   40 |     int cnt = 1;
      |         ^~~

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