oj.uz

Submission #477797

# Submission time Handle Problem Language Result Execution time Memory
477797 2021-10-03T19:52:28 Z mychecksedad Trener (COCI20_trener) C++17
110 / 110
 824 ms 40904 KB 
/* Author : Mychecksdead */
#include<bits/stdc++.h>
using namespace std;
typedef long long int ll;
typedef long double ld;
#define MOD (1000000000+7)
#define MOD1 (998244353)
#define PI 3.1415926535
#define pb push_back
#define setp() cout << setprecision(15)
#define all(x) x.begin(), x.end()
const int N = 1e6+100, M = 1e5+10, F = 2147483646, K = 20;


ll fp(ll a, ll b){
    ll res = 1;
    while(b){
        if(b & 1) (res *= a) %= MOD;
        (a*=a)%=MOD;
        b>>=1;
    }
    return res;
}
int n, k;
ll dp[55][1600], h[55][1600][55];
string s[55][1600];
void solve(){
    cin >> n >> k;
    for(int i = 1; i <= n; ++i) for(int j = 1; j <= k; ++j) cin >> s[i][j];
    for(int i = 1; i <= n; ++i){
        for(int j = 1; j <= k; ++j){
            h[i][j][0] = 0;
            ll e = 1;
            for(int c = 1; c <= i; ++c, (e*=31)%=MOD){
                h[i][j][c] = (h[i][j][c - 1] + e * (s[i][j][c - 1] - 'a')) % MOD;
            }
        }
    }
    for(int i = 0; i <= n; i++) for(int j = 0; j <= k; ++j) dp[i][j] = 0;
    for(int j = 1; j <= k; ++j) dp[1][j] = 1;
    ll f = fp(31 * 1LL, MOD-2);
    for(int i = 2; i <= n; ++i){
        for(int j = 1; j <= k; ++j){
            for(int back = 1; back <= k; ++back){
                ll l = h[i][j][i - 1];
                ll r = ((((h[i][j][i] - h[i][j][1]) * f)%MOD)+MOD)%MOD;
                if(l == h[i - 1][back][i - 1] || r == h[i - 1][back][i - 1]){
                    (dp[i][j] += dp[i - 1][back]) %= MOD;
                } 
            }
        }
    }
    ll sum = 0;
    for(int i = 1; i <= k; ++i) (sum += dp[n][i]) %= MOD;
    cout << sum;
}



int main(){
    cin.tie(0); ios::sync_with_stdio(0);
    int T = 1, aa;
    // cin >> T;aa=T;
    while(T--){
        // cout << "Case #" << aa-T << ": ";
        solve();
    }
    return 0;
 
}

Compilation message

trener.cpp: In function 'int main()':
trener.cpp:62:16: warning: unused variable 'aa' [-Wunused-variable]
   62 |     int T = 1, aa;
      |                ^~

Subtask #1
22.0 / 22.0

# Verdict Execution time Memory Grader output
1 Correct 2 ms 3148 KB Output is correct
2 Correct 1 ms 3148 KB Output is correct
3 Correct 2 ms 3148 KB Output is correct
4 Correct 2 ms 3148 KB Output is correct

Subtask #2
33.0 / 33.0

# Verdict Execution time Memory Grader output
1 Correct 5 ms 5836 KB Output is correct
2 Correct 4 ms 5836 KB Output is correct
3 Correct 4 ms 5836 KB Output is correct
4 Correct 7 ms 5940 KB Output is correct
5 Correct 5 ms 5836 KB Output is correct
6 Correct 4 ms 5836 KB Output is correct
7 Correct 7 ms 5836 KB Output is correct

Subtask #3
55.0 / 55.0

# Verdict Execution time Memory Grader output
1 Correct 2 ms 3148 KB Output is correct
2 Correct 1 ms 3148 KB Output is correct
3 Correct 2 ms 3148 KB Output is correct
4 Correct 2 ms 3148 KB Output is correct
5 Correct 5 ms 5836 KB Output is correct
6 Correct 4 ms 5836 KB Output is correct
7 Correct 4 ms 5836 KB Output is correct
8 Correct 7 ms 5940 KB Output is correct
9 Correct 5 ms 5836 KB Output is correct
10 Correct 4 ms 5836 KB Output is correct
11 Correct 7 ms 5836 KB Output is correct
12 Correct 159 ms 38920 KB Output is correct
13 Correct 166 ms 40788 KB Output is correct
14 Correct 167 ms 40896 KB Output is correct
15 Correct 160 ms 40884 KB Output is correct
16 Correct 814 ms 40884 KB Output is correct
17 Correct 188 ms 40880 KB Output is correct
18 Correct 189 ms 40880 KB Output is correct
19 Correct 199 ms 40880 KB Output is correct
20 Correct 192 ms 40880 KB Output is correct
21 Correct 196 ms 40904 KB Output is correct
22 Correct 824 ms 40876 KB Output is correct