Submission #602535

#	Time	Username	Problem	Language	Result	Execution time	Memory
602535		SamAnd	Misspelling (JOI22_misspelling)	C++17	100 / 100	478 ms	136108 KiB

misspelling

#include <bits/stdc++.h>
using namespace std;
#define m_p make_pair
#define all(x) (x).begin(),(x).end()
#define sz(x) ((int)(x).size())
#define fi first
#define se second
typedef long long ll;
mt19937 rnd(chrono::steady_clock::now().time_since_epoch().count());
mt19937 rnf(2106);
const int N = 500005, M = 1000000007;

int n, m;
int a[N];

vector<int> v[N];

int dp[N][26][2];

void solv()
{
    cin >> n >> m;
    for (int i = 1; i <= m; ++i)
    {
        int x, y;
        cin >> x >> y;
        if (x == y)
            continue;
        if (x < y)
        {
            v[x].push_back(y);
        }
        else
        {
            v[y].push_back(-x);
        }
    }

    stack<int> g[2];

    int s[26] = {};
    for (int k = 0; k < 26; ++k)
    {
        dp[n][k][0] = 1;
        s[k] = 1;
    }
    for (int i = n - 1; i >= 1; --i)
    {
        /*for (int k = 0; k < 26; ++k)
        {
            for (int j = i + 1; j <= n; ++j)
            {
                s[k] = (s[k] + dp[j][k][0]) % M;
                s[k] = (s[k] + dp[j][k][1]) % M;
            }
        }*/
        int p[26] = {};
        p[0] = s[0];
        for (int k = 1; k < 26; ++k)
            p[k] = (p[k - 1] + s[k]) % M;
        for (int k = 0; k < 26; ++k)
        {
            dp[i][k][1] = (p[25] - p[k] + M) % M;
            if (k)
                dp[i][k][0] = p[k - 1];
            s[k] = (s[k] + dp[i][k][1]) % M;
            s[k] = (s[k] + dp[i][k][0]) % M;
            /*for (int u = k + 1; u < 26; ++u)
                dp[i][k][1] = (dp[i][k][1] + s[u]) % M;
            for (int u = 0; u < k; ++u)
                dp[i][k][0] = (dp[i][k][0] + s[u]) % M;*/
        }
        g[0].push(i);
        g[1].push(i);
        for(int t = 0; t < sz(v[i]); ++t)
        {
            if (v[i][t] > 0)
            {
                while (!g[1].empty())
                {
                    int j = g[1].top();
                    if (j < v[i][t])
                    {
                        for (int k = 0; k < 26; ++k)
                        {
                            s[k] = (s[k] - dp[j][k][1] + M) % M;
                            dp[j][k][1] = 0;
                        }
                        g[1].pop();
                    }
                    else
                        break;
                }
            }
            else
            {
                while (!g[0].empty())
                {
                    int j = g[0].top();
                    if (j < -v[i][t])
                    {
                        for (int k = 0; k < 26; ++k)
                        {
                            s[k] = (s[k] - dp[j][k][0] + M) % M;
                            dp[j][k][0] = 0;
                        }
                        g[0].pop();
                    }
                    else
                        break;
                }
            }
        }
    }

    int ans = 0;
    for (int k = 0; k < 26; ++k)
        ans = (ans + s[k]) % M;

    cout << ans << "\n";
}

int main()
{
    #ifdef SOMETHING
    freopen("input.txt", "r", stdin);
    //freopen("output.txt", "w", stdout);
    #endif // SOMETHING
    ios_base::sync_with_stdio(false), cin.tie(0);

    int tt = 1;
    //cin >> tt;
    while (tt--)
    {
        solv();
    }
    return 0;
}

• Subtask 1: 8 / 8
• Subtask 2: 20 / 20
• Subtask 3: 29 / 29
• Subtask 4: 32 / 32
• Subtask 5: 11 / 11