Submission #1188362

#	Time	Username	Problem	Language	Result	Execution time	Memory
1188362		kl0989e	Genetics (BOI18_genetics)	C++20	74 / 100	2093 ms	86700 KiB

genetics

#include <bits/stdc++.h>
using namespace std;

#define ll long long
#define fi first
#define se second
#define pb push_back
#define vi vector<int>
#define vl vector<ll>
#define pi pair<int, int>
#define pl pair<ll,ll>
#define all(x) (x).begin(),(x).end()

vector<string> s;
vector<vi> dif;
vi ok;
int n,m,k;

int diff(int i, int j) {
	if (dif[i][j]!=-1) {
		return dif[i][j];
	}
	int cnt=0;
	for (int l=0; l<m; l++) {
		if (s[i][l]!=s[j][l]) {
			cnt++;
		}
	}
	dif[i][j]=cnt;
	dif[j][i]=cnt;
	if (cnt!=k) {
		ok[i]=0;
		ok[j]=0;
	}
	return cnt;
}

int32_t main() {
	ios::sync_with_stdio(0);
	cin.tie(0);
	cin >> n >> m >> k;
	s.resize(n);
	dif.resize(n,vi(n,-1));
	ok.resize(n,1);
	for (int i=0; i<n; i++) {
		cin >> s[i];
	}
	vector<map<char,int>> cnts(m);
	for (int i=0; i<n; i++) {
		for (int j=0; j<m; j++) {
			cnts[j][s[i][j]]++;
		}
	}
	mt19937 rnd(time(0));
	vi ord1(n);
	iota(all(ord1),0);
	shuffle(all(ord1),rnd);
	for (auto i:ord1) {
		if (!ok[i]) {
			continue;
		}
		int tot=0;
		for (int j=0; j<m; j++) {
			tot+=n-cnts[j][s[i][j]];
		}
		if (tot!=k*(n-1)) {
			continue;
		}
		vi ord(n);
		iota(all(ord),0);
		shuffle(all(ord),rnd);
		for (auto j:ord) {
			if (i==j) {
				continue;
			}
			if (diff(i,j)!=k) {
				break;
			}
		}
		if (ok[i]) {
			cout << i+1 << '\n';
			return 0;
		}
	}
	return 0;
}

• Subtask 1: 27 / 27
• Subtask 2: 19 / 19
• Subtask 3: 28 / 28
• Subtask 4: 0 / 26