Submission #373088

#	Time	Username	Problem	Language	Result	Execution time	Memory
373088		Nimbostratus	Trener (COCI20_trener)	C++17	110 / 110	864 ms	40772 KiB

trener

#include <bits/stdc++.h>
using namespace std;
#define eb emplace_back
#define pb push_back
#define ppb pop_back
#define ub upper_bound
#define lb lower_bound
#define bs binary_search
#define cln(a,s) memset((a),0,sizeof((a)[0])*(s))
#define all(x) (x).begin() , (x).end()
#define fi first
#define se second
#define int long long
using pii = pair<int,int>;
using ll = long long;
const int maxn = 55;
const int maxk = 1505;
const int inf = 1e9;
const int mod = 1e9+7;
const int hmod = 1e9+9;

int n,k;
string a[maxn][maxk];
int dp[maxn][maxk],hsh[maxn][maxk][maxn];
//a[i][j] 1 indexli
//stringler 0 indexli
//dp 1 indexli
//hsh[][] 1 indexli , stringler 0 indexli olduğu için hsh[][] 0 indexli

int32_t main () {
	//freopen("in","r",stdin); freopen("out","w",stdout);
	ios_base::sync_with_stdio(0); cout.tie(0); cin.tie(0);
	cin >> n >> k;
	for(int i=1;i<=n;i++)
		for(int j=1;j<=k;j++) {
			cin >> a[i][j];
			string tmp = a[i][j];
			hsh[i][j][0] = tmp[0]-'a'+1;
			int pow = 1;
			for(int m=1;m<i;m++) {
				pow *= 31;
				pow %= hmod;
				hsh[i][j][m] = hsh[i][j][m-1] + pow*(tmp[m]-'a'+1);
				hsh[i][j][m] %= hmod; 
			}
			//cout << i << " " << j << " " << hsh[i][j][i-1] << endl;
		}
	for(int i=1;i<=k;i++) dp[1][i] = 1;
	for(int i=2;i<=n;i++)
		for(int j=1;j<=k;j++) {
			int h1 = hsh[i][j][i-2];
			int h2 = hsh[i][j][i-1] - hsh[i][j][0];
			//cout << a[i][j] << " " << h1 << " " << h2 << endl;
			h2 += 2*hmod;
			h2 %= hmod;
			for(int m=1;m<=k;m++) {
				if(hsh[i-1][m][i-2] == h1) {
					dp[i][j] += dp[i-1][m];
					dp[i][j] %= mod;
				}
				else if((31*hsh[i-1][m][i-2])%hmod == h2) {
					dp[i][j] += dp[i-1][m];
					dp[i][j] %= mod;
				}
			}
		}
	int ans = 0;
	for(int i=1;i<=k;i++) {
		ans += dp[n][i];
		ans %= mod;
	}
	cout << ans << endl;
}

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