Submission #432373

#	Time	Username	Problem	Language	Result	Execution time	Memory
432373		tengiz05	Miners (IOI07_miners)	C++17	52 / 100	1401 ms	1816 KiB

miners

#include <bits/stdc++.h>
std::mt19937 rng(std::chrono::steady_clock::now().time_since_epoch().count());
int main() {
    std::ios::sync_with_stdio(false);
    std::cin.tie(nullptr);
    int n;
    std::cin >> n;
    std::string s;
    std::cin >> s;
    std::vector<int> a(n);
    for (int i = 0; i < n; i++) {
        if (s[i] == 'M') a[i] = 0;
        if (s[i] == 'F') a[i] = 1;
        if (s[i] == 'B') a[i] = 2;
    }
    if (n <= 2) {
        int ans = 0;
        for (int msk = 0; msk < (1 << n); msk++) {
            int res = 0;
            std::vector<int> ca(3), cb(3);
            std::vector<int> A, B;
            for (int i = 0; i < n; i++) {
                if (msk & (1 << i)) {
                    if (A.size() >= 3) {
                        ca[A[A.size() - 3]]--;
                    }
                    A.push_back(a[i]);
                    ca[a[i]]++;
                    res += bool(ca[0]) + bool(ca[1]) + bool(ca[2]);
                } else {
                    if (B.size() >= 3) {
                        cb[B[B.size() - 3]]--;
                    }
                    B.push_back(a[i]);
                    cb[a[i]]++;
                    res += bool(cb[0]) + bool(cb[1]) + bool(cb[2]);
                }
            }
            ans = std::max(ans, res);
        }
        std::cout << ans << "\n";
    } else {
        int ans = 0;
        std::bitset<100000> b;
        while (1.0 * std::clock() / CLOCKS_PER_SEC < 1.4) {
            for (int i = 0; i < n; i++) {
                b[i] = rng() & 1;
            }
            int res = 0;
            std::vector<int> ca(3), cb(3);
            std::vector<int> A, B;
            for (int i = 0; i < n; i++) {
                if (b[i]) {
                    if (A.size() >= 3) {
                        ca[A[A.size() - 3]]--;
                    }
                    A.push_back(a[i]);
                    ca[a[i]]++;
                    res += bool(ca[0]) + bool(ca[1]) + bool(ca[2]);
                } else {
                    if (B.size() >= 3) {
                        cb[B[B.size() - 3]]--;
                    }
                    B.push_back(a[i]);
                    cb[a[i]]++;
                    res += bool(cb[0]) + bool(cb[1]) + bool(cb[2]);
                }
            }
            ans = std::max(ans, res);
        }
        std::cout << ans << "\n";
    }
    return 0;
}

• Subtask 1: 9 / 9
• Subtask 2: 9 / 9
• Subtask 3: 9 / 9
• Subtask 4: 9 / 9
• Subtask 5: 9 / 9
• Subtask 6: 7 / 7
• Subtask 7: 0 / 8
• Subtask 8: 0 / 8
• Subtask 9: 0 / 8
• Subtask 10: 0 / 8
• Subtask 11: 0 / 8
• Subtask 12: 0 / 8