Submission #366171

#	Time	Username	Problem	Language	Result	Execution time	Memory
366171		ngpin04	Miners (IOI07_miners)	C++11	100 / 100	122 ms	101200 KiB

miners

#include <bits/stdc++.h>

using namespace std;
const int N = 1e5 + 5;

int n;
int a[N];
int dp[N][4][4][4][4];

void maxi(int &a, int b)
{
    if (a < b)
        a = b;
}

int cost(int a, int b, int c)
{
    int res = 0;
    if (a < 3)
        res++;
    if (b < 3 && a != b)
        res++;
    if (c < 3 && a != c && b != c)
        res++;
    return res;
}

int main()
{
    ios_base::sync_with_stdio(0);
    cin.tie(0);
    //freopen("file.inp","r",stdin);
    cin >> n;
    for (int i = 1; i <= n; i++)
    {
        char c;
        cin >> c;
        if (c == 'B')
            a[i] = 0;
        else if (c == 'M')
            a[i] = 1;
        else
            a[i] = 2;
    }

    memset(dp, -1, sizeof(dp));

    dp[1][3][3][3][3] = 0;

    int ans = 0;
    for (int i = 1; i <= n; i++)
    for (int x = 0; x <= 3; x++)
    for (int y = 0; y <= 3; y++)
    for (int u = 0; u <= 3; u++)
    for (int v = 0; v <= 3; v++)
    {
        int cur = dp[i][x][y][u][v];
        if (cur < 0)
            continue;
        maxi(dp[i + 1][y][a[i]][u][v], cur + cost(x, y, a[i]));
        maxi(dp[i + 1][x][y][v][a[i]], cur + cost(u, v, a[i]));
        if (i == n)
        {
            maxi(ans, dp[i + 1][y][a[i]][u][v]);
            maxi(ans, dp[i + 1][x][y][v][a[i]]);
        }
    }

    cout << ans;
    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