Submission #219371

#	Time	Username	Problem	Language	Result	Execution time	Memory
219371		kartel	Trener (COCI20_trener)	C++14	110 / 110	1148 ms	114760 KiB

trener

#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 optimize("Ofast")
#pragma GCC optimize("unroll-loops")
#pragma GCC optimize("-O3")
#define F first
#define S second
#define pb push_back
#define N +400500
#define M ll(1e9 + 7)
#define sz(x) (int)x.size()
#define re return
#define oo ll(1e18)
#define el '\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;

bool go[51][1501][1501];
ll f[51][1501], ans, hsh[51][1501], p[51];
int i, j, k, m, p1, n;
string s[51][1501];

ll sm(ll x, ll y) {return (x + y) % M;}

int main()
{
    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 >> m;
    p[0] = 1;
    for (i = 1; i <= n; i++) p[i] = (p[i - 1] * 31) % M;
    for (i = 1; i <= n; i++)
        for (j = 1; j <= m; j++)
        {
            cin >> s[i][j];
            hsh[i][j] = 0;
            for (k = 0; k < i; k++)
                hsh[i][j] = sm(hsh[i][j], (s[i][j][k] - 'a' + 1) * p[k] % M);
        }
    for (i = 1; i < n; i++)
    {
        for (j = 1; j <= m; j++)
        {
            for (k = 1; k <= m; k++)
            {
                if (hsh[i][j] * 31 % M == (hsh[i + 1][k] - (s[i + 1][k][0] - 'a' + 1) + M) % M) go[i][j][k] = 1;
                if (hsh[i][j] == (M + hsh[i + 1][k] - (s[i + 1][k][i] - 'a' + 1) * p[i] % M) % M) go[i][j][k] = 1;
            }
        }
    }
    for (i = 1; i <= m; i++) f[1][i] = 1;
    for (i = 1; i < n; i++)
        for (j = 1; j <= m; j++)
          for (k = 1; k <= m; k++)
            if (go[i][j][k]) f[i + 1][k] = sm(f[i][j], f[i + 1][k]);

    ans = 0;
    for (i = 1; i <= m; i++) ans = sm(f[n][i], ans);
    cout << ans;
}

• Subtask 1: 22 / 22
• Subtask 2: 33 / 33
• Subtask 3: 55 / 55