Submission #883609

#	Time	Username	Problem	Language	Result	Execution time	Memory
883609		mgl_diamond	Trener (COCI20_trener)	C++17	110 / 110	169 ms	8568 KiB

trener

#include <bits/stdc++.h>
using namespace std;
using ll = long long;
using ii = pair<ll, ll>;
 
#define foru(i, l, r) for(int i=(l); i<=(r); ++i)
#define ford(i, l, r) for(int i=(l); i>=(r); --i)
#define fore(x, v) for(auto &x : v)
#define all(x) (x).begin(), (x).end()
#define sz(x) (int)(x).size()
#define fi first
#define se second
#define file "input"

template<class T> bool minimize(T &a, T b) { if (a > b) { a = b; return 1; } return 0; }
template<class T> bool maximize(T &a, T b) { if (a < b) { a = b; return 1; } return 0; }

void setIO() {
  ios::sync_with_stdio(0);
  cin.tie(0); cout.tie(0);
  if (fopen(file".inp", "r")) {
    freopen(file".inp", "r", stdin);
    freopen(file".out", "w", stdout);
  }
}

const int MOD = 1e9+7, B = 256;
const int N = 51, K = 1501;
int n, k, dp[N][K];
int one[N][K], two[N][K];
string s[N][K];

int mul(int a, int b) {
  return 1LL * a * b % MOD;
}

void add(int &a, int b) {
  a += b;
  if (a >= MOD) a -= MOD;
}

int main() {
  setIO();

  cin >> n >> k;
  foru(i, 1, n) foru(j, 1, k) {
    cin >> s[i][j];
    foru(c, 0, i-2) one[i][j] = (1LL * one[i][j] * B % MOD + s[i][j][c]) % MOD;
    foru(c, 1, i-1) two[i][j] = (1LL * two[i][j] * B % MOD + s[i][j][c]) % MOD;
  }

  foru(i, 1, k) dp[1][i] = 1;
  foru(i, 1, n) {
    foru(j, 1, k) if (dp[i][j] > 0) {
      int hsh = 0;
      fore(c, s[i][j]) hsh = (1LL * hsh * B % MOD + c) % MOD;
      foru(c, 1, k) if (hsh == one[i+1][c] || hsh == two[i+1][c]) 
        add(dp[i+1][c], dp[i][j]);
    }
  }

  int ans = 0;
  foru(i, 1, k) add(ans, dp[n][i]);
  cout << ans;
}

Compilation message (stderr)

trener.cpp: In function 'void setIO()':
trener.cpp:22:12: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
   22 |     freopen(file".inp", "r", stdin);
      |     ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~
trener.cpp:23:12: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
   23 |     freopen(file".out", "w", stdout);
      |     ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~

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