Submission #432062

#	Time	Username	Problem	Language	Result	Execution time	Memory
432062		MilosMilutinovic	Miners (IOI07_miners)	C++14	100 / 100	1371 ms	844 KiB

miners

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

int dp[2][4][4][4][4];

int count_diff(int x, int y, int z) {
    set<int> values;

    if (x != 0) values.insert(x);
    if (y != 0) values.insert(y);
    if (z != 0) values.insert(z);

    return values.size();
}

void clear_dp(int par) {
    for (int d1 = 0; d1 <= 3; d1++)
        for (int d2 = 0; d2 <= 3; d2++)
            for (int d3 = 0; d3 <= 3; d3++)
                for (int d4 = 0; d4 <= 3; d4++)
                    dp[par][d1][d2][d3][d4] = -1e9;
}

int main() {
    ios::sync_with_stdio(false);
    cin.tie(nullptr);

    int N;
    cin >> N;
    string S;
    cin >> S;

    vector<int> A(N);
    for (int i = 0; i < N; i++) {
        if (S[i] == 'M') A[i] = 1;
        if (S[i] == 'F') A[i] = 2;
        if (S[i] == 'B') A[i] = 3;
    }

    int val = A[0];

    clear_dp(0);

    dp[0][A[0]][A[0]][0][0] = 1;
    dp[0][0][0][A[0]][A[0]] = 1;

    for (int i = 1; i < N; i++) {
        int curr = i & 1, prev = curr ^ 1, d = A[i];
        clear_dp(curr);

        int start = (i <= 8 ? 0 : 1);
        for (int d1 = start; d1 <= 3; d1++)
            for (int d2 = start; d2 <= 3; d2++)
                for (int d3 = start; d3 <= 3; d3++)
                    for (int d4 = start; d4 <= 3; d4++) {
                        dp[curr][d][d1][d3][d4] =  max(dp[curr][d][d1][d3][d4], dp[prev][d1][d2][d3][d4] + count_diff(d, d1, d2));
                        dp[curr][d1][d2][d][d3] =  max(dp[curr][d1][d2][d][d3], dp[prev][d1][d2][d3][d4] + count_diff(d, d3, d4));
                    }
    }

    int answer = 0;
    for (int d1 = 1; d1 <= 3; d1++)
        for (int d2 = 1; d2 <= 3; d2++)
            for (int d3 = 1; d3 <= 3; d3++)
                for (int d4 = 1; d4 <= 3; d4++)
                    answer = max(answer, dp[(N - 1) & 1][d1][d2][d3][d4]);

    cout << answer << '\n';
    return 0;
}

Compilation message (stderr)

miners.cpp: In function 'int main()':
miners.cpp:40:9: warning: unused variable 'val' [-Wunused-variable]
   40 |     int val = A[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