Submission #887065

#	Time	Username	Problem	Language	Result	Execution time	Memory
887065		chanhchuong123	Trener (COCI20_trener)	C++14	110 / 110	150 ms	3740 KiB

trener

#include <bits/stdc++.h>
using namespace std;
#define task "MAKELIST"
#define all(x) (x).begin(), (x).end()
#define rall(x) (x).rbegin(), (x).rend()

const int MOD = 1e9 + 7;
int n, k;
int dp[55][1505];
int hh[55][1505][3];

int main() {
	ios_base::sync_with_stdio(false); cin.tie(nullptr);

	if (fopen(task".inp", "r")) {
		freopen(task".inp", "r",  stdin);
		freopen(task".out", "w", stdout);
	}

    cin >> n >> k;
    for (int i = 1; i <= n; ++i) {
        for (int j = 1; j <= k; ++j) {
            string s;
            cin >> s;
            for (int l = 0, r = max(0, i - 2); r < i; ++l, ++r) {
                int hashing = 0;
                for (int k = l; k <= r; ++k) {
                    hashing = 29LL * hashing % MOD;
                    hashing += s[k] - 'a' + 1;
                    hashing %= MOD;
                }
                if (i == 1) {
                    hh[i][j][2] = hashing;
                    continue;
                }
                hh[i][j][l] = hashing;
                if (l == 0) {
                    hashing = 29LL * hashing % MOD;
                    hashing += s.back() - 'a' + 1;
                    hashing %= MOD;
                    hh[i][j][2] = hashing;
                }
            }
        }
    }

    for (int j = 1; j <= k; ++j) {
        dp[1][j] = 1;
    }
    for (int i = 1; i < n; ++i) {
        for (int a = 1; a <= k; ++a) if (dp[i][a]) {
            for (int b = 1; b <= k; ++b) if (hh[i][a][2] == hh[i + 1][b][0] || hh[i][a][2] == hh[i + 1][b][1]) {
                dp[i + 1][b] += dp[i][a];
                if (dp[i + 1][b] >= MOD)
                    dp[i + 1][b] -= MOD;
            }
        }
    }

    int res = 0;
    for (int j = 1; j <= k; ++j) {
        res += dp[n][j];
        if (res >= MOD)
            res -= MOD;
    }
    cout << res;

	return 0;
}

Compilation message (stderr)

trener.cpp: In function 'int main()':
trener.cpp:16:10: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
   16 |   freopen(task".inp", "r",  stdin);
      |   ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~
trener.cpp:17:10: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
   17 |   freopen(task".out", "w", stdout);
      |   ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~

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