Submission #739430

#	Time	Username	Problem	Language	Result	Execution time	Memory
739430		Alihan_8	Boat (APIO16_boat)	C++17	9 / 100	4 ms	2288 KiB

boat

#include <bits/stdc++.h>

using namespace std;

#define all(x) x.begin(), x.end()
#define pb push_back
#define ln '\n'
#define int long long

template <class _T>
bool chmin(_T &x, const _T &y){
    bool flag = false;
    if ( x > y ){
        x = y; flag |= true;
    }
    return flag;
}

template <class _T>
bool chmax(_T &x, const _T &y){
    bool flag = false;
    if ( x < y ){
        x = y; flag |= true;
    }
    return flag;
}

signed main(){
    ios_base::sync_with_stdio(false);
    cin.tie(nullptr);

    int n; cin >> n;
    vector <int> a(n), b(n), pos;
    for ( int i = 0; i < n; i++ ){
        cin >> a[i] >> b[i];
        pos.pb(a[i]); pos.pb(b[i]);
    }
    sort(all(pos));
    pos.resize(unique(all(pos)) - pos.begin());
    auto id = [&](int x){
        return lower_bound(all(pos), x) - pos.begin() + 1;
    };
    const int Mod = 1e9 + 7;
    auto add = [&](int &x, const int &y){
        x = (x + y) % Mod;
        if ( x < 0 ) x += Mod;
    };
    vector <vector<int>> dp(n + 1, vector <int> (n + 1));
    dp[0][0] = 1;
    for ( int i = 1; i <= n; i++ ){
        int v = id(a[i - 1]);
        for ( int j = 0; j <= n; j++ ){
            dp[i][j] = dp[i - 1][j];
        }
        for ( int k = 0; k < v; k++ ){
            add(dp[i][v], dp[i - 1][k]);
        }
    }
    int cnt = 0;
    for ( int i = 1; i <= n; i++ ){
        add(cnt, dp[n][i]);
    }
    cout << cnt;

    cout << '\n';
}

• Subtask 1: 9 / 9
• Subtask 2: 0 / 22
• Subtask 3: 0 / 27
• Subtask 4: 0 / 42