Submission #1340467

#	Time	Username	Problem	Language	Result	Execution time	Memory
1340467		kawhiet	Miners (IOI07_miners)	C++20	100 / 100	434 ms	836 KiB

miners

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

int dp[4][4][4][4];
int dp_nxt[4][4][4][4];

int main() {
    ios::sync_with_stdio(false);
    cin.tie(nullptr);
    int n;
    string s;
    cin >> n >> s;
    vector<int> a(n);
    for (int i = 0; i < n; i++) {
        if (s[i] == 'M') {
            a[i] = 1;
        } else if (s[i] == 'B') {
            a[i] = 2;
        } else {
            a[i] = 3;
        }
    }
    auto get = [&](int x, int y, int z) {
        set<int> s = {x, y, z};
        if (*s.begin() == 0) {
            s.erase(s.begin());
        }
        return (int)s.size();
    };
    dp[0][a[0]][0][0] = 1;
    dp[0][0][0][a[0]] = 1;
    for (int i = 1; i < n; i++) {
        for (int x1 = 0; x1 < 4; x1++) {
            for (int y1 = 0; y1 < 4; y1++) {
                for (int x2 = 0; x2 < 4; x2++) {
                    for (int y2 = 0; y2 < 4; y2++) {
                        dp_nxt[x1][y1][x2][y2] = 0;
                    }
                }
            }
        }
        for (int x1 = 0; x1 < 4; x1++) {
            for (int y1 = 0; y1 < 4; y1++) {
                for (int x2 = 0; x2 < 4; x2++) {
                    for (int y2 = 0; y2 < 4; y2++) {
                        int k = dp[x1][y1][x2][y2];
                        if (k == 0) continue;
                        dp_nxt[x1][y1][y2][a[i]] = max(dp_nxt[x1][y1][y2][a[i]], k + get(x2, y2, a[i]));
                        dp_nxt[y1][a[i]][x2][y2] = max(dp_nxt[y1][a[i]][x2][y2], k + get(x1, y1, a[i]));
                    }
                }
            }
        }
        swap(dp, dp_nxt);
    }
    int ans = 0;
    for (int i = 0; i < 4; i++) {
        for (int j = 0; j < 4; j++) {
            for (int x = 0; x < 4; x++) {
                for (int y = 0; y < 4; y++) {
                    ans = max(ans, dp[i][j][x][y]);
                }
            }
        }
    }
    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: 8 / 8
• Subtask 8: 8 / 8
• Subtask 9: 8 / 8
• Subtask 10: 8 / 8
• Subtask 11: 8 / 8
• Subtask 12: 8 / 8