Submission #252788

#	Time	Username	Problem	Language	Result	Execution time	Memory
252788		kartel	Savez (COCI15_savez)	C++14	120 / 120	187 ms	59128 KiB

savez

#include <bits/stdc++.h>
//#include <ext/pb_ds/assoc_container.hpp>
//#include <ext/pb_ds/tree_policy.hpp>
#define in(x) freopen(x, "r", stdin)
#define out(x) freopen(x, "w", stdout)
//#pragma GCC target("sse,sse2,sse3,ssse3,sse4,popcnt,abm,mmx,avx,tune=native")
//#pragma GCC optimize("Ofast,nso-stack-protector,unroll-loops,fast-math,-O3")
//#define F first
//#define S second
#define pb push_back
#define N +2000500
#define M ll(1e9 + 7)
#define sz(x) (int)x.size()
#define re return
#define oo ll(1e9)
#define el '\n'
#define Max_A int(1e9)
//#define el endl
#define pii pair <int, int>
#define err ld(1e-9)
#define Max_S int(3e6)
#define last(x) x.back()
#define all(x) (x).begin(), (x).end()
#define arr_all(x, n) (x + 1), (x + 1 + n)
using namespace std;
//using namespace __gnu_pbds;
//typedef tree <int, null_type, less_equal <int> , rb_tree_tag, tree_order_statistics_node_update> ordered_set;
typedef long long ll;
typedef long double ld;

int st, n, i, ans, rev;
unordered_map <int, int> f;


int mult(ll x, ll y){return (x * y) % M;}
int sum(ll x, ll y) {return (x + y + M) % M;}

ll bp(ll x, ll y)
{
    if (y == 0) return 1ll;
    if (y % 2) return mult(bp(x, y - 1), x);
    ll a = bp(x, y / 2);
    return mult(a, a);
}

int dv(ll x) {return (mult(x, rev));}

int main()
{
    cout.precision(2);
    srand(time(0));
    ios_base::sync_with_stdio(0);
    iostream::sync_with_stdio(0);
    ios::sync_with_stdio(0);
    cin.tie(NULL);
    cout.tie(NULL);

//    in("input.txt");
//    out("output.txt");

    cin >> n;
    int siz[n + 1];
    vector <int> hsh[n + 1];
    string s;

    for (i = 1; i <= n; i++)
        {
            cin >> s;
            siz[i] = sz(s);
            hsh[i].resize(siz[i]);
            hsh[i][0] = s[0] - 'A' + 1;
            st = 1;
            for (int j = 1; j < siz[i]; j++)
                {
                    st = mult(st, 31);
                    hsh[i][j] = sum(hsh[i][j - 1], mult(st, s[j] - 'A' + 1));
                }
        }

    rev = bp(31, M - 2);

    for (i = 1; i <= n; i++)
    {
        f[hsh[i][siz[i] - 1]]++;

        st = 1;

        for (int j = 0; j < siz[i] - 1; j++)
            st = mult(st, 31);

        for (int j = 0; j < siz[i] - 1; j++)
            {
//                cerr << mult(hsh[i][j], st) << " " << sum(hsh[i][siz[i] - 1], -hsh[i][siz[i] - j - 2]) << el;

                if (mult(hsh[i][j], st) == sum(hsh[i][siz[i] - 1], -hsh[i][siz[i] - j - 2]))

                f[hsh[i][siz[i] - 1]] = max(f[hsh[i][j]] + 1, f[hsh[i][siz[i] - 1]]);

                st = dv(st);
            }

        ans = max(ans, f[hsh[i][siz[i] - 1]]);
    }
    cout << ans;
}
/*
961 961
1953 1023
1922 1922
1984 1984
923521 923521
1876833 983103
984064 984064
1878786 984126
28629151 57258302
29552672 58181823
29582463 58211614
29583424 58212575
29583455 58212606
*/
//
//00000
//00110
//00111
//00011
//00000

• Subtask 1: 12 / 12
• Subtask 2: 12 / 12
• Subtask 3: 12 / 12
• Subtask 4: 12 / 12
• Subtask 5: 12 / 12
• Subtask 6: 12 / 12
• Subtask 7: 12 / 12
• Subtask 8: 12 / 12
• Subtask 9: 12 / 12
• Subtask 10: 12 / 12