Submission #760665

#	Time	Username	Problem	Language	Result	Execution time	Memory
760665		GrindMachine	Genetics (BOI18_genetics)	C++17	100 / 100	901 ms	149016 KiB

genetics

// Om Namah Shivaya

#include <bits/stdc++.h>
#include <ext/pb_ds/assoc_container.hpp>
#include <ext/pb_ds/tree_policy.hpp>

using namespace std;
using namespace __gnu_pbds;

template<typename T> using Tree = tree<T, null_type, less<T>, rb_tree_tag, tree_order_statistics_node_update>;
typedef long long int ll;
typedef long double ld;
typedef pair<int, int> pii;
typedef pair<ll, ll> pll;

#define fastio ios_base::sync_with_stdio(false); cin.tie(NULL)
#define pb push_back
#define endl '\n'
#define sz(a) a.size()
#define setbits(x) __builtin_popcountll(x)
#define ff first
#define ss second
#define conts continue
#define ceil2(x, y) ((x + y - 1) / (y))
#define all(a) a.begin(), a.end()
#define rall(a) a.rbegin(), a.rend()
#define yes cout << "Yes" << endl
#define no cout << "No" << endl

#define rep(i, n) for(int i = 0; i < n; ++i)
#define rep1(i, n) for(int i = 1; i <= n; ++i)
#define rev(i, s, e) for(int i = s; i >= e; --i)
#define trav(i, a) for(auto &i : a)

template<typename T>
void amin(T &a, T b) {
    a = min(a, b);
}

template<typename T>
void amax(T &a, T b) {
    a = max(a, b);
}

#ifdef LOCAL
#include "debug.h"
#else
#define debug(x) 42
#endif

/*

refs:
edi

*/

const int MOD = 1e9 + 7;
const int N = 4100 + 5;
const int inf1 = int(1e9) + 5;
const ll inf2 = ll(1e18) + 5;

vector<int> ps = {5791, 8237, 3067, 6991, 3527};
vector<int> mods = {791139137, 433567597, 271149607, 561259969, 222708581};
ll pows[N][2];

void precalc() {
    mt19937 rng(chrono::steady_clock::now().time_since_epoch().count());

    shuffle(all(ps), rng);
    shuffle(all(mods), rng);

    rep(j, 2) {
        pows[0][j] = 1;
        rep1(i, N - 1) {
            pows[i][j] = pows[i - 1][j] * ps[j] % mods[j];
        }
    }
}

void solve(int test_case)
{
    precalc();

    ll n,m,k; cin >> n >> m >> k;
    ll a[n+5][m+5];

    rep1(i,n){
        rep1(j,m){
            char ch; cin >> ch;
            ll x = 0;

            if(ch == 'A') x = 0;
            if(ch == 'C') x = 1;
            if(ch == 'G') x = 2;
            if(ch == 'T') x = 3;

            a[i][j] = x;
        }
    } 

    mt19937 rng(chrono::steady_clock::now().time_since_epoch().count());
    auto random = [&](ll l, ll r){
        return uniform_int_distribution<ll>(l,r)(rng);
    };

    vector<pll> w(n+5);
    rep1(i,n){
        w[i].ff = random(1,mods[0]-1);
        w[i].ss = random(1,mods[1]-1);
    }

    pll want = {0,0};
    rep1(i,n){
        want.ff += (w[i].ff * k);
        want.ff %= mods[0];
        want.ss += (w[i].ss * k);
        want.ss %= mods[1];
    }

    pll col_sum[m+5][4];
    memset(col_sum,0,sizeof col_sum);

    rep1(i,n){
        rep1(j,m){
            ll ch = a[i][j];
            col_sum[j][ch].ff = (col_sum[j][ch].ff + w[i].ff) % mods[0];
            col_sum[j][ch].ss = (col_sum[j][ch].ss + w[i].ss) % mods[1];
        }
    }

    rep1(i,n){
        pll sum = {0,0};

        rep1(j,m){
            rep(ch,4){
                if(ch != a[i][j]){
                    sum.ff = (sum.ff + col_sum[j][ch].ff) % mods[0];
                    sum.ss = (sum.ss + col_sum[j][ch].ss) % mods[1];
                }
            }
        }

        sum.ff = (sum.ff + w[i].ff * k) % mods[0];
        sum.ss = (sum.ss + w[i].ss * k) % mods[1];

        if(sum == want){
            cout << i << endl;
            return;
        }
    }

    assert(0);
}

int main()
{
    fastio;

    int t = 1;
    // cin >> t;

    rep1(i, t) {
        solve(i);
    }

    return 0;
}

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