Submission #114254

#	Time	Username	Problem	Language	Result	Execution time	Memory
114254		popovicirobert	Miners (IOI07_miners)	C++14	100 / 100	152 ms	632 KiB

miners

#include <bits/stdc++.h>
#define lsb(x) (x & (-x))
#define ll long long
#define ull unsigned long long
// 217
// 44

using namespace std;

const int MAXN = (int) 1e5;

char str[MAXN + 1];

int dp[4][4][4][4], aux[4][4][4][4];
char id[256];

int sol[4][4][4];

inline int get(int a, int b, int c) {
    if(sol[a][b][c] > 0)
        return sol[a][b][c];

    vector <int> arr;
    if(a > 0) arr.push_back(a);
    if(b > 0) arr.push_back(b);
    if(c > 0) arr.push_back(c);

    sort(arr.begin(), arr.end());
    arr.resize(unique(arr.begin(), arr.end()) - arr.begin());

    return sol[a][b][c] = arr.size();
}


int main() {
    //ifstream cin("A.in");
    //ofstream cout("A.out");
    int n, i;
    ios::sync_with_stdio(false);
    cin.tie(0), cout.tie(0);

    cin >> n >> str + 1;

    for(int a = 0; a < 4; a++) {
        for(int b = 0; b < 4; b++) {
            for(int c = 0; c < 4; c++) {
                for(int d = 0; d < 4; d++) {
                    dp[a][b][c][d] = -3 * n;
                }
            }
        }
    }

    id['M'] = 1, id['F'] = 2, id['B'] = 3;
    dp[0][0][0][0] = 0;

    for(i = 0; i < n; i++) {
        for(int a = 0; a < 4; a++) {
            for(int b = 0; b < 4; b++) {
                for(int c = 0; c < 4; c++) {
                    for(int d = 0; d < 4; d++) {
                        aux[a][b][c][d] = -3 * n;
                    }
                }
            }
        }
        for(int a = 0; a < 4; a++) {
            for(int b = 0; b < 4; b++) {
                for(int c = 0; c < 4; c++) {
                    for(int d = 0; d < 4; d++) {
                        int cur = id[str[i + 1]];
                        aux[b][cur][c][d] = max(aux[b][cur][c][d], dp[a][b][c][d] + get(a, b, cur));
                        aux[a][b][d][cur] = max(aux[a][b][d][cur], dp[a][b][c][d] + get(c, d, cur));
                    }
                }
            }
        }

        memcpy(dp, aux, sizeof(aux));
    }

    int ans = 0;
    for(int a = 0; a < 4; a++) {
        for(int b = 0; b < 4; b++) {
            for(int c = 0; c < 4; c++) {
                for(int d = 0; d < 4; d++) {
                    ans = max(ans, dp[a][b][c][d]);
                }
            }
        }
    }

    cout << ans;

    //cin.close();
    //cout.close();
    return 0;
}

Compilation message (stderr)

miners.cpp: In function 'int main()':
miners.cpp:42:21: warning: suggest parentheses around '+' inside '>>' [-Wparentheses]
     cin >> n >> str + 1;
                 ~~~~^~~
miners.cpp:71:48: warning: array subscript has type 'char' [-Wchar-subscripts]
                         int cur = id[str[i + 1]];
                                                ^

• 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