Submission #860938

#	Time	Username	Problem	Language	Result	Execution time	Memory
860938		GordonRemzi007	Martian DNA (BOI18_dna)	C++17	16 / 100	390 ms	1048576 KiB

dna

#include <iostream>
#include <vector>
#include <map>
#include <climits>
#define int long long

using namespace std;

signed main() {
    int n, k, r, res, le, ri, mid, ans;
    bool ok;
    map<int,int> c;
    cin >> n >> k >> r;
    vector<int> a(n);
    vector<pair<int,int>> b(r);
    vector<vector<int>> prefix(n, vector<int>(r));
    for(int i = 0; i < n; i++) cin >> a[i];
    for(int i = 0; i < r; i++) {
        cin >> b[i].first >> b[i].second;
        c[b[i].first] = i+1;
    }
    if(c[a[0]]) prefix[0][c[a[0]]-1]++;
    for(int i = 1; i < n; i++) {
        for(int j = 0; j < r; j++) prefix[i][j] = prefix[i-1][j];
        if(c[a[i]]) prefix[i][c[a[i]]-1]++;
    }
    for(int z = 0; z < r; z++) {
        if(prefix[n-1][z] < b[z].second) {
            cout << "impossible\n";
            return 0;
        }
    }
    res = n;
    for(int i = 0; i < n; i++) {
        le = i, ri = n, ans = LLONG_MAX;
        while(le<ri) {
            mid = (le+ri)/2;
            ok = true;
            for(int j = 0; j < r; j++) {
                if(prefix[mid][j]-(i == 0 ? 0 : prefix[i-1][j]) < b[j].second) {
                    ok = false;
                    break;
                }
            }
            if(ok) {
                ri = mid-1;
                ans = mid;
            }
            else le = mid+1;
        }
        res = min(res, ans-i+1);
    }
    cout << res << "\n";
}

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