Submission #1002128

#	Time	Username	Problem	Language	Result	Execution time	Memory
1002128		vjudge1	Dabbeh (INOI20_dabbeh)	C++17	25 / 100	2055 ms	197976 KiB

Main

#include <bits/stdc++.h>

using namespace std;

// #define int long long
#define ll long long
#define pii pair<ll, ll>
#define all(v) v.begin(), v.end()
#define oo 1e9
const int MAX = 5e5 + 5, B = 61, MOD1 = 1e9 + 7, MOD2 = 1e9 + 9, LOGMAX = 21;
struct ST{
    pii tree[4 * MAX];
    void init(){
        for(int i = 0; i < 4 * MAX; i++) tree[i] = {0, 0};
    }
    void update(int node, int l, int r, int pos, pii val){
        if(l == r){
            tree[node] = val;
            return;
        }
        int mid = (l + r) / 2;
        if(pos <= mid) update(2 * node, l, mid, pos, val);
        else update(2 * node + 1, mid + 1, r, pos, val);
        tree[node] = max(tree[2 * node], tree[2 * node + 1]);
    }
    pii ask(int node, int l, int r, int ql, int qr){
        if(qr < l || r < ql) return {0, 0};
        if(ql <= l && r <= qr) return tree[node];
        int mid = (l + r) / 2;
        return max(ask(2 * node, l, mid, ql, qr), ask(2 * node + 1, mid + 1, r, ql, qr));
    }
};
int binpow(int a, int b, int m){
    if(b == 0) return 1;
    if(b & 1) return 1ll * binpow(a, b - 1, m) % m * a % m;
    return 1ll * binpow(1ll * a * a % m, b / 2, m) % m;
}
int inv(int a, int m){
    return binpow(a, m - 2, m);
}
int n, q;
string s;
string t[MAX];

map<pii, int> mp;
pii pre[MAX];
pii P[(int)5e5 + 5];
pii invP[(int)5e5 + 5];
ST st;
int par[LOGMAX][MAX];
int nxt[MAX];

pii calc(int l, int r){
    return {1ll * (pre[r].first - pre[l - 1].first + 2ll * MOD1) % MOD1 * invP[l - 1].first % MOD1,
            1ll * (pre[r].second - pre[l - 1].second + 2ll * MOD2) % MOD2 * invP[l - 1].second % MOD2};
}


void solve(){
    P[0]= {1, 1};
    invP[0] = {1, 1};
    for(int i = 1; i <= 5e5; i++){
        P[i].first = 1ll * P[i - 1].first * B % MOD1;
        P[i].second = 1ll * P[i - 1].second * B % MOD2;
        invP[i].first = 1ll * invP[i - 1].first * inv(B, MOD1) % MOD1;
        invP[i].second = 1ll * invP[i - 1].second * inv(B, MOD2) % MOD2;
    }
    cin >> n >> q;
    for(int i = 1; i <= n; i++){
        cin >> t[i];
        pii H = {0, 0};
        for(int j = 0; j < t[i].size(); j++){
            H.first = (H.first + 1ll * (t[i][j] - 'a' + 1) * P[j].first % MOD1) % MOD1;
            H.second = (H.second + 1ll * (t[i][j] - 'a' + 1) * P[j].second % MOD2) % MOD2;
            mp[H] = 1;
        }
    }
    cin >> s;
    n = s.size();
    for(int i = 1; i <= n; i++){
        pre[i].first = (pre[i - 1].first + 1ll * (s[i - 1] - 'a' + 1) * P[i - 1].first % MOD1) % MOD1;
        pre[i].second = (pre[i - 1].second + 1ll * (s[i - 1] - 'a' + 1) * P[i - 1].second % MOD2) % MOD2;
    }
    st.init();
    st.update(1, 1, n + 1, n + 1, {n + 1, n + 1});
    par[0][n + 1] = n + 1;
    nxt[n + 1] = n + 1;
    for(int i = n; i >= 1; i--){
        if(!mp[calc(i, i)]){
            par[0][i] = i;
            nxt[i] = i;
            st.update(1, 1, n + 1, i, {i, i});
            continue;
        }
        int l = i, r = n;
        while(l < r){
            int mid = (l + r + 1) / 2;
            if(mp[calc(i, mid)]) l = mid;   
            else r = mid - 1;
        }
        par[0][i] = st.ask(1, 1, n + 1, i + 1, l + 1).second;
        nxt[i] = l + 1;
        st.update(1, 1, n + 1, i, {l + 1, i});
    }
    for(int j = 1; j < LOGMAX; j++){
        for(int i = 1; i <= n + 1; i++){
            par[j][i] = par[j - 1][par[j - 1][i]];
        }
    }
    while(q--){
        int l, r; cin >> l >> r;
        l++;
        if(nxt[l] > r){
            cout << "1\n";
            continue;
        }
        ll ans = 0;
        for(int i = LOGMAX - 1; i >= 0; i--){
            if(nxt[par[i][l]] <= r){
                ans += (1ll << i);
                l = par[i][l];
            }
        }
        if(nxt[par[0][l]] <= r) cout << "-1\n";
        else cout << ans + 2 << '\n';
    }
}

signed main(){
    ios::sync_with_stdio(0);
    cin.tie(0);
    cout.tie(0);
    int t = 1;
    while(t--){
        solve();
    }
}

Compilation message (stderr)

Main.cpp: In function 'void solve()':
Main.cpp:72:26: warning: comparison of integer expressions of different signedness: 'int' and 'std::__cxx11::basic_string<char>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   72 |         for(int j = 0; j < t[i].size(); j++){
      |                        ~~^~~~~~~~~~~~~

• Subtask 1: 25 / 25
• Subtask 2: 0 / 25
• Subtask 3: 0 / 50