oj.uz

Submission #830969

# Submission time Handle Problem Language Result Execution time Memory
830969 2023-08-19T14:11:59 Z vjudge1 Exam (eJOI20_exam) C++17
100 / 100
 414 ms 102344 KB 
#include <bits/stdc++.h>
#include <ext/pb_ds/assoc_container.hpp>
#include <ext/pb_ds/tree_policy.hpp>

#pragma GCC target ("avx2")
#pragma GCC optimization ("O3")
#pragma GCC optimization ("unroll-loops")
#pragma comment(linker, "/stack:200000000")
#pragma GCC target("sse,sse2,sse3,ssse3,sse4,popcnt,abm,mmx,avx,tune=native")
//turn on extra precision
//#pragma GCC target("fpmath=387")

using namespace std;
using namespace __gnu_pbds;

using str   = string;
using ll    = long long;
using pii   = pair <int,int>;
using pll   = pair <ll,ll>;
using vi    = vector <int>;
using vll   = vector <ll>;
using vpii  = vector <pii>;
using vpll  = vector <pll>;

template<class A, class B>
ostream& operator<<(ostream& os, const pair<A, B> &p) {
    os << '(' << p.first << ',' << p.second << ')';
    return os;
}

template<class T>
ostream& operator<<(ostream& os, const vector<T> &v) {
    bool van = 1; os << '{';
    for(auto &i : v) { if(!van) os << ", "; os << i; van = 0; }
    os << '}'; return os;
}

template<class T, size_t sz>
ostream& operator<<(ostream&os, const array<T,sz> &arr) {
    bool fs = 1; os << '{';
    for(auto &i : arr) { if(!fs) os << ", "; os << i; fs = 0; }
    os << '}'; return os;
}

#define mp make_pair
#define fi first
#define se second
#define fs first.second
#define ss second.second
#define ff first.first
#define sf second.first
#define newl '\n'
#define all(x) x.begin(), x.end()
#define watch(x) cerr << (#x) << " is : " << (x) << newl

mt19937_64 rng(chrono::steady_clock::now().time_since_epoch().count());

template <class T>
ll quickpow(ll num1, ll num2, const T MOD) {
    assert(num2 >= 0); ll ans = 1;
    for(; num2; num2>>=1, num1 = num1 * num1 % MOD) if(num2 & 1) ans = ans * num1 % MOD;
    return ans;
}
// end of Template

int main(){

    ios_base::sync_with_stdio(false);
    cin.tie(NULL);

    int n; cin >> n;
    vector<int> a(n+1), b(n+1);
    for(int i = 1; i <= n; ++i) cin >> a[i];
    for(int i = 1; i <= n; ++i) cin >> b[i];

    const auto sub2 = [&b, &n]() -> bool {
        for(int i = 2; i <= n; ++i) if(b[i] != b[i-1]) return false;
        return true;
    };

    const auto sub4 = [&a, &n]() -> bool {
        set<int> s;
        for(int i = 1; i <= n; ++i) s.emplace(a[i]);
        return s.size() == n;
    };

    if(sub2()) {
        bool hasb = false;
        int len = 0;

        int res = 0;
        for(int i = 1; i <= n; ++i) {
            if(a[i] > b[i]) {
                res += hasb * len;
                len = 0;
                hasb = false;
                continue;
            }

            ++len;
            if(a[i] == b[i]) hasb = true;
        }

        res += hasb * len;
        return cout << res << newl, 0;
    }

    if(sub4()) {
        map<int,int> pos;
        for(int i = 1; i <= n; ++i) pos[a[i]] = i;

        class sparseTable {
            private:
                vector<vector<int>> st;
                int n;
            public:
                sparseTable(vector<int> &v) : n(v.size() - 1) {
                    st.emplace_back(vector<int>(n+1));
                    for(int i = 1; i <= n; ++i) st[0][i] = v[i];

                    for(int i = 1; (1<<i) <= n; ++i) {
                        st.emplace_back(vector<int>(n+1));
                        for(int j = 1; j + (1<<i) - 1 <= n; ++j) {
                            st[i][j] = max(st[i-1][j], st[i-1][j+(1<<(i-1))]);
                        }
                    }
                }

                int getMin(int l, int r) {
                    int lv = __lg(r - l + 1);
                    return max(st[lv][l], st[lv][r-(1<<lv)+1]);
                }
        };

        class fenwick {
            private:
                vector<int> BIT;
                int n;
            public:
                fenwick(int n) : n(n) {
                    BIT.resize(n+1);
                }
                void update(int idx, int val) {
                    for(int i = idx; i <= n; i += i & -i) BIT[i] = max(BIT[i], val);
                    return;
                }
                int getMax(int idx) {
                    int res = 0;
                    for(int i = idx; i; i -= i & -i) res = max(res, BIT[i]);
                    return res;
                }
        };

        sparseTable sparse(a);
        fenwick BIT(n);

        int ans = 0;
        for(int i = 1; i <= n; ++i) {
            if(!pos.count(b[i])) continue;
            if(sparse.getMin(min(i, pos[b[i]]), max(i, pos[b[i]])) > b[i]) continue;

            int res = 1 + BIT.getMax(pos[b[i]]);
            BIT.update(pos[b[i]], res);
            ans = max(ans, res);
        }

        return cout << ans << newl, 0;
    }

    vector<vector<bool>> can(n+1, vector<bool>(n+1));
    for(int i = 1; i <= n; ++i) {
        can[i][i] = true;
        for(int mx = a[i], j = i - 1; j; --j) {
            mx = max(mx, a[j]);
            can[i][j] = (mx == a[j]);
        }
        for(int mx = a[i], j = i + 1; j <= n; ++j) {
            mx = max(mx, a[j]);
            can[i][j] = (mx == a[j]);
        }
    }

    vector<vector<int>> memo(n+1, vector<int>(n+1, -1));
    const auto dp = [&](const auto &self, int id1, int id2) -> int {
        if(id1 < 1 || id2 < 1) return 0;
        int &res = memo[id1][id2];
        if(~res) return res;
        res = 0;

        if(b[id2] == a[id1] && can[id2][id1]) {
            res = max(res, 1 + self(self, id1, id2 - 1));
        }
        else {
            res = max(res, self(self, id1 - 1, id2));
            res = max(res, self(self, id1, id2 - 1));
        }

        return res;
    };

    cout << dp(dp, n, n) << newl;

    return 0;
}

Compilation message

exam.cpp:6: warning: ignoring '#pragma GCC optimization' [-Wunknown-pragmas]
    6 | #pragma GCC optimization ("O3")
      | 
exam.cpp:7: warning: ignoring '#pragma GCC optimization' [-Wunknown-pragmas]
    7 | #pragma GCC optimization ("unroll-loops")
      | 
exam.cpp:8: warning: ignoring '#pragma comment ' [-Wunknown-pragmas]
    8 | #pragma comment(linker, "/stack:200000000")
      | 
exam.cpp: In lambda function:
exam.cpp:84:25: warning: comparison of integer expressions of different signedness: 'std::set<int>::size_type' {aka 'long unsigned int'} and 'int' [-Wsign-compare]
   84 |         return s.size() == n;
      |                ~~~~~~~~~^~~~

Subtask #1
14.0 / 14.0

# Verdict Execution time Memory Grader output
1 Correct 0 ms 212 KB Output is correct
2 Correct 0 ms 212 KB Output is correct
3 Correct 1 ms 212 KB Output is correct
4 Correct 1 ms 212 KB Output is correct
5 Correct 1 ms 212 KB Output is correct
6 Correct 0 ms 324 KB Output is correct

Subtask #2
12.0 / 12.0

# Verdict Execution time Memory Grader output
1 Correct 1 ms 212 KB Output is correct
2 Correct 3 ms 468 KB Output is correct
3 Correct 10 ms 980 KB Output is correct
4 Correct 8 ms 1108 KB Output is correct
5 Correct 16 ms 1108 KB Output is correct
6 Correct 9 ms 1108 KB Output is correct
7 Correct 12 ms 1124 KB Output is correct
8 Correct 15 ms 1108 KB Output is correct

Subtask #3
13.0 / 13.0

# Verdict Execution time Memory Grader output
1 Correct 0 ms 212 KB Output is correct
2 Correct 1 ms 340 KB Output is correct
3 Correct 1 ms 468 KB Output is correct
4 Correct 3 ms 724 KB Output is correct
5 Correct 3 ms 852 KB Output is correct
6 Correct 3 ms 852 KB Output is correct

Subtask #4
23.0 / 23.0

# Verdict Execution time Memory Grader output
1 Correct 3 ms 852 KB Output is correct
2 Correct 35 ms 5204 KB Output is correct
3 Correct 95 ms 12784 KB Output is correct
4 Correct 101 ms 12836 KB Output is correct
5 Correct 104 ms 12872 KB Output is correct
6 Correct 82 ms 12872 KB Output is correct
7 Correct 77 ms 12864 KB Output is correct
8 Correct 92 ms 12844 KB Output is correct
9 Correct 105 ms 12748 KB Output is correct
10 Correct 72 ms 12868 KB Output is correct

Subtask #5
16.0 / 16.0

# Verdict Execution time Memory Grader output
1 Correct 0 ms 212 KB Output is correct
2 Correct 0 ms 212 KB Output is correct
3 Correct 1 ms 212 KB Output is correct
4 Correct 1 ms 212 KB Output is correct
5 Correct 1 ms 212 KB Output is correct
6 Correct 0 ms 324 KB Output is correct
7 Correct 0 ms 212 KB Output is correct
8 Correct 0 ms 212 KB Output is correct
9 Correct 1 ms 340 KB Output is correct
10 Correct 1 ms 468 KB Output is correct
11 Correct 1 ms 468 KB Output is correct
12 Correct 1 ms 468 KB Output is correct
13 Correct 1 ms 468 KB Output is correct
14 Correct 1 ms 452 KB Output is correct

Subtask #6
22.0 / 22.0

# Verdict Execution time Memory Grader output
1 Correct 0 ms 212 KB Output is correct
2 Correct 0 ms 212 KB Output is correct
3 Correct 1 ms 212 KB Output is correct
4 Correct 1 ms 212 KB Output is correct
5 Correct 1 ms 212 KB Output is correct
6 Correct 0 ms 324 KB Output is correct
7 Correct 0 ms 212 KB Output is correct
8 Correct 1 ms 340 KB Output is correct
9 Correct 1 ms 468 KB Output is correct
10 Correct 3 ms 724 KB Output is correct
11 Correct 3 ms 852 KB Output is correct
12 Correct 3 ms 852 KB Output is correct
13 Correct 0 ms 212 KB Output is correct
14 Correct 0 ms 212 KB Output is correct
15 Correct 1 ms 340 KB Output is correct
16 Correct 1 ms 468 KB Output is correct
17 Correct 1 ms 468 KB Output is correct
18 Correct 1 ms 468 KB Output is correct
19 Correct 1 ms 468 KB Output is correct
20 Correct 1 ms 452 KB Output is correct
21 Correct 1 ms 468 KB Output is correct
22 Correct 11 ms 4556 KB Output is correct
23 Correct 1 ms 340 KB Output is correct
24 Correct 414 ms 102320 KB Output is correct
25 Correct 303 ms 102228 KB Output is correct
26 Correct 276 ms 102268 KB Output is correct
27 Correct 292 ms 102212 KB Output is correct
28 Correct 271 ms 102344 KB Output is correct
29 Correct 277 ms 102284 KB Output is correct
30 Correct 270 ms 102328 KB Output is correct
31 Correct 272 ms 102164 KB Output is correct
32 Correct 276 ms 102332 KB Output is correct