Submission #793630

#	Time	Username	Problem	Language	Result	Execution time	Memory
793630		vjudge1	Misspelling (JOI22_misspelling)	C++17	100 / 100	1457 ms	171344 KiB

misspelling

#include <bits/stdc++.h>

#define fi first
#define se second

const int N = 500500;
const int mod = 1e9 + 7;

using namespace std;

void add(int &x, int y) {
    x += y;
    if (x >= mod) {
        x -= mod;
    } else if (x < 0) {
        x += mod;
    }
}

int n;
int m;
int d[N][26];
int s[N][26];
vector<int> A[N], B[N];

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

    cin >> n >> m;
    for (int i = 1; i <= m; i++) {
        int a, b;
        cin >> a >> b;
        if (a == b) {
            continue;
        }

        if (a < b) {
            A[a].push_back(b);
        } else {
            B[b].push_back(a);
        }
    }

    for (int i = 0; i < 26; i++) {
        d[1][i] = s[1][i] = 1;
    }

    set<pair<int, int>> S, T;

    for (int i = 2; i <= n; i++) {
        for (int j: A[i - 1]) {
            S.insert({i - 1, j});
        }
        for (int j: B[i - 1]) {
            T.insert({i - 1, j});
        }
        while (!S.empty() && (--S.end())->se < i) {
            S.erase(--S.end());
        }
        while (!T.empty() && (--T.end())->se < i) {
            T.erase(--T.end());
        }
        int p_1 = S.empty() ? 0 : (--S.end())->fi;
        int p_2 = T.empty() ? 0 : (--T.end())->fi;
        for (int j = 0; j < 26; j++) {
            for (int h = 0; h < j; h++) {
                add(d[i][j], s[i - 1][h] - s[max(p_1, p_2)][h]);
                if (p_1 < p_2) {
                    add(d[i][j], s[p_2][h] - s[p_1][h]);
                }
            }
            for (int h = j + 1; h < 26; h++) {
                add(d[i][j], s[i - 1][h] - s[max(p_1, p_2)][h]);
                if (p_1 > p_2) {
                    add(d[i][j], s[p_1][h] - s[p_2][h]);
                }
            }

            s[i][j] = s[i - 1][j];
            add(s[i][j], d[i][j]);
        }
    }

    int res = 0;
    for (int i = 0; i < 26; i++) {
        add(res, s[n][i]);
    }

    cout << res << "\n";
}

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