oj.uz

Submission #483231

# Submission time Handle Problem Language Result Execution time Memory
483231 2021-10-28T10:20:00 Z Monarchuwu Global Warming (CEOI18_glo) C++17
100 / 100
 353 ms 25920 KB 
/**
 *  tăng giảm 1 đoạn bất kì 1 lượng |d| <= x để lis đạt max
 *  - nhận xét: kmttq, giả sử tăng 1 đoạn [i,j] lên k đơn vị thì tăng cả ở prefix lẫn suffix
 *      + điều này vô lý vì xét case hi[1]-lo-hi[2], lo vốn đã match với hi[2], nếu tăng lo thêm thì lis chỉ có thể giảm đi
 *  => ta update lại hết prefix hoặc suffix, đồng thời nhận xét là ta luôn tăng hoặc giảm hết mức (tăng giảm x đơn vị)
 *  => chỉ xét giảm prefix đi x (tăng suffix lên x có cấu hình sau khi nén số tương tự)
**/
#include<iostream>
#include<algorithm>
#include<vector>
#include<unordered_map>
using namespace std;
typedef long long ll;

const int N = 2e5 + 8;
const int N2 = N << 1;

int n, x;
int t[N];

vector<int> a;
unordered_map<int, int> mp;

void build_map() {
    for (int i = 1; i <= n; ++i)
        a.push_back(t[i]), a.push_back(t[i] - x);
    sort(a.begin(), a.end());
    a.resize(unique(a.begin(), a.end()) - a.begin());

    int cnt(0);
    for (int x : a) mp[x] = ++cnt;
}

int dp[2][N]; // prefix, suffix, max suffix
int b[N];

int bit[N2];
void upd(int p, int v) { for (; p <= a.size(); p += p & -p) bit[p] = max(bit[p], v); }
int get(int p) { int ans(0); for (; p; p ^= p & -p) ans = max(ans, bit[p]); return ans; }

int main() {
    ios_base::sync_with_stdio(false); cin.tie(NULL);
    cin >> n >> x;
    for (int i = 1; i <= n; ++i)
        cin >> t[i];
    build_map();

    int cnt(0);
    for (int i = 1, p; i <= n; ++i) {
        dp[0][i] = p = lower_bound(b + 1, b + cnt + 1, mp[t[i]]) - b;
        if (cnt < p) cnt = p;
        b[p] = mp[t[i]];
    }

    cnt = 0;
    for (int i = n, p; i > 0; --i) {
        dp[1][i] = p = lower_bound(b + 1, b + cnt + 1, mp[t[i]], greater<int>()) - b;
        if (cnt < p) cnt = p;
        b[p] = mp[t[i]];
    }

    int ans(0);
    for (int i = 1; i <= n; ++i) {
        ans = max(ans, get(mp[t[i]] - 1) + dp[1][i]);
        upd(mp[t[i] - x], dp[0][i]);
    }
    cout << ans << '\n';
}

Compilation message

glo.cpp: In function 'void upd(int, int)':
glo.cpp:38:35: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   38 | void upd(int p, int v) { for (; p <= a.size(); p += p & -p) bit[p] = max(bit[p], v); }
      |                                 ~~^~~~~~~~~~~

Subtask #1
5.0 / 5.0

# Verdict Execution time Memory Grader output
1 Correct 0 ms 332 KB Output is correct
2 Correct 0 ms 332 KB Output is correct
3 Correct 0 ms 332 KB Output is correct
4 Correct 0 ms 332 KB Output is correct
5 Correct 1 ms 332 KB Output is correct
6 Correct 0 ms 324 KB Output is correct
7 Correct 0 ms 332 KB Output is correct
8 Correct 1 ms 328 KB Output is correct
9 Correct 0 ms 332 KB Output is correct
10 Correct 0 ms 332 KB Output is correct
11 Correct 0 ms 332 KB Output is correct

Subtask #2
10.0 / 10.0

# Verdict Execution time Memory Grader output
1 Correct 0 ms 332 KB Output is correct
2 Correct 0 ms 332 KB Output is correct
3 Correct 0 ms 332 KB Output is correct
4 Correct 0 ms 332 KB Output is correct
5 Correct 1 ms 332 KB Output is correct
6 Correct 0 ms 324 KB Output is correct
7 Correct 0 ms 332 KB Output is correct
8 Correct 1 ms 328 KB Output is correct
9 Correct 0 ms 332 KB Output is correct
10 Correct 0 ms 332 KB Output is correct
11 Correct 0 ms 332 KB Output is correct
12 Correct 1 ms 332 KB Output is correct
13 Correct 1 ms 244 KB Output is correct
14 Correct 1 ms 328 KB Output is correct
15 Correct 0 ms 332 KB Output is correct
16 Correct 0 ms 324 KB Output is correct
17 Correct 0 ms 328 KB Output is correct
18 Correct 0 ms 332 KB Output is correct

Subtask #3
13.0 / 13.0

# Verdict Execution time Memory Grader output
1 Correct 0 ms 332 KB Output is correct
2 Correct 0 ms 332 KB Output is correct
3 Correct 0 ms 332 KB Output is correct
4 Correct 0 ms 332 KB Output is correct
5 Correct 1 ms 332 KB Output is correct
6 Correct 0 ms 324 KB Output is correct
7 Correct 0 ms 332 KB Output is correct
8 Correct 1 ms 328 KB Output is correct
9 Correct 0 ms 332 KB Output is correct
10 Correct 0 ms 332 KB Output is correct
11 Correct 0 ms 332 KB Output is correct
12 Correct 1 ms 332 KB Output is correct
13 Correct 1 ms 244 KB Output is correct
14 Correct 1 ms 328 KB Output is correct
15 Correct 0 ms 332 KB Output is correct
16 Correct 0 ms 324 KB Output is correct
17 Correct 0 ms 328 KB Output is correct
18 Correct 0 ms 332 KB Output is correct
19 Correct 1 ms 460 KB Output is correct
20 Correct 1 ms 460 KB Output is correct
21 Correct 1 ms 468 KB Output is correct
22 Correct 1 ms 332 KB Output is correct
23 Correct 1 ms 332 KB Output is correct
24 Correct 1 ms 332 KB Output is correct
25 Correct 1 ms 332 KB Output is correct
26 Correct 1 ms 332 KB Output is correct

Subtask #4
10.0 / 10.0

# Verdict Execution time Memory Grader output
1 Correct 190 ms 14024 KB Output is correct
2 Correct 188 ms 15852 KB Output is correct
3 Correct 186 ms 15876 KB Output is correct
4 Correct 188 ms 15864 KB Output is correct
5 Correct 74 ms 10808 KB Output is correct

Subtask #5
20.0 / 20.0

# Verdict Execution time Memory Grader output
1 Correct 46 ms 6168 KB Output is correct
2 Correct 41 ms 6624 KB Output is correct
3 Correct 43 ms 6644 KB Output is correct
4 Correct 20 ms 4088 KB Output is correct
5 Correct 0 ms 332 KB Output is correct
6 Correct 14 ms 4084 KB Output is correct
7 Correct 32 ms 5320 KB Output is correct

Subtask #6
17.0 / 17.0

# Verdict Execution time Memory Grader output
1 Correct 126 ms 11708 KB Output is correct
2 Correct 152 ms 12676 KB Output is correct
3 Correct 353 ms 25008 KB Output is correct
4 Correct 128 ms 15084 KB Output is correct
5 Correct 45 ms 12380 KB Output is correct
6 Correct 94 ms 23856 KB Output is correct
7 Correct 88 ms 24500 KB Output is correct
8 Correct 98 ms 12636 KB Output is correct

Subtask #7
25.0 / 25.0

# Verdict Execution time Memory Grader output
1 Correct 0 ms 332 KB Output is correct
2 Correct 0 ms 332 KB Output is correct
3 Correct 0 ms 332 KB Output is correct
4 Correct 0 ms 332 KB Output is correct
5 Correct 1 ms 332 KB Output is correct
6 Correct 0 ms 324 KB Output is correct
7 Correct 0 ms 332 KB Output is correct
8 Correct 1 ms 328 KB Output is correct
9 Correct 0 ms 332 KB Output is correct
10 Correct 0 ms 332 KB Output is correct
11 Correct 0 ms 332 KB Output is correct
12 Correct 1 ms 332 KB Output is correct
13 Correct 1 ms 244 KB Output is correct
14 Correct 1 ms 328 KB Output is correct
15 Correct 0 ms 332 KB Output is correct
16 Correct 0 ms 324 KB Output is correct
17 Correct 0 ms 328 KB Output is correct
18 Correct 0 ms 332 KB Output is correct
19 Correct 1 ms 460 KB Output is correct
20 Correct 1 ms 460 KB Output is correct
21 Correct 1 ms 468 KB Output is correct
22 Correct 1 ms 332 KB Output is correct
23 Correct 1 ms 332 KB Output is correct
24 Correct 1 ms 332 KB Output is correct
25 Correct 1 ms 332 KB Output is correct
26 Correct 1 ms 332 KB Output is correct
27 Correct 190 ms 14024 KB Output is correct
28 Correct 188 ms 15852 KB Output is correct
29 Correct 186 ms 15876 KB Output is correct
30 Correct 188 ms 15864 KB Output is correct
31 Correct 74 ms 10808 KB Output is correct
32 Correct 46 ms 6168 KB Output is correct
33 Correct 41 ms 6624 KB Output is correct
34 Correct 43 ms 6644 KB Output is correct
35 Correct 20 ms 4088 KB Output is correct
36 Correct 0 ms 332 KB Output is correct
37 Correct 14 ms 4084 KB Output is correct
38 Correct 32 ms 5320 KB Output is correct
39 Correct 126 ms 11708 KB Output is correct
40 Correct 152 ms 12676 KB Output is correct
41 Correct 353 ms 25008 KB Output is correct
42 Correct 128 ms 15084 KB Output is correct
43 Correct 45 ms 12380 KB Output is correct
44 Correct 94 ms 23856 KB Output is correct
45 Correct 88 ms 24500 KB Output is correct
46 Correct 98 ms 12636 KB Output is correct
47 Correct 115 ms 13004 KB Output is correct
48 Correct 119 ms 13008 KB Output is correct
49 Correct 340 ms 25920 KB Output is correct
50 Correct 113 ms 15576 KB Output is correct
51 Correct 51 ms 10988 KB Output is correct
52 Correct 65 ms 15712 KB Output is correct
53 Correct 97 ms 24804 KB Output is correct
54 Correct 90 ms 25396 KB Output is correct
55 Correct 207 ms 20660 KB Output is correct