Submission #957400

#	Time	Username	Problem	Language	Result	Execution time	Memory
957400		vjudge1	Martian DNA (BOI18_dna)	C++17	40 / 100	796 ms	1048576 KiB

dna

#include<bits/stdc++.h>

using namespace std;

#define ll long long
#define fi first
#define se second
#define pii pair<int, int>
#define pll pair<ll, ll>

const ll N = 200069;
const ll mod = 1e9 + 7;

int tc;
ll n, k, r;

int main()
{
    ios_base::sync_with_stdio(0);cin.tie(0);cout.tie(0);
    ll i, j;
    
    cin >> n >> k >> r;
    ll pref[n+1][k+1];
    memset(pref, 0, sizeof(pref));
    for(i = 1; i <= n; i++)
    {
        for(j = 0; j < k; j++) pref[i][j] = pref[i-1][j];
        ll x;
        cin >> x;
        ++pref[i][x];
    }

    ll need[k+1];
    memset(need, 0, sizeof(need));
    bool bisa = 1;
    ll sm = 0;
    for(i = 1; i <= r; i++)
    {
        ll x, y;
        cin >> x >> y;
        need[x] = y;
        sm += y;
        if(need[x] > pref[n][x])
        {
            bisa = 0;
        }
    }
    if(!bisa)
    {
        cout << "impossible" << '\n';
        return 0;
    }

    ll ans = n;
    for(i = sm; i <= n; i++)
    {
        ll cn = 0;
        for(j = 0; j < k; j++) cn += pref[i][j] >= need[j];
        if(cn == k)
        {
            ll l = 0, r = i;
            while(l <= r)
            {
                ll mid = (l + r)/2;
                ll res = 0;
                for(j = 0; j < k; j++) res += pref[i][j] - pref[mid][j] >= need[j];
                if(res == k)
                {
                    ans = min(ans, i - mid);
                    l = mid + 1;
                }
                else r = mid - 1;
            }
        }
    }
    cout << ans << '\n';
}

• Subtask 1: 16 / 16
• Subtask 2: 24 / 24
• Subtask 3: 0 / 28
• Subtask 4: 0 / 32