Submission #166141

#	Time	Username	Problem	Language	Result	Execution time	Memory
166141		gabrc52	Miners (IOI07_miners)	C++14	100 / 100	693 ms	110200 KiB

miners

#include <iostream>
#include <unordered_map>
#include <cstring>

using namespace std;

const int MAXN = 100000;
char shipment[MAXN + 2];
int N;

int memo[MAXN][4][4][4][4];

struct Prev {
	char a[2][2];
};

Prev give(int pos, int mine, Prev prev) {
	prev.a[mine][0] = prev.a[mine][1];
	prev.a[mine][1] = shipment[pos];
	return prev;
}

int diff(int pos, int mine, Prev prev) {
	int foodCount[150] = {0};
	foodCount[prev.a[mine][0]]++;
	foodCount[prev.a[mine][1]]++;
	foodCount[shipment[pos]]++;
	int typesOfFood = 0;
	if (foodCount['M'])
		typesOfFood++;
	if (foodCount['F'])
		typesOfFood++;
	if (foodCount['B'])
		typesOfFood++;
	return typesOfFood;
}

int conversion[150];

int F(int pos, Prev prev) {
	if (pos == N) {
		return 0;
	} else {
		int &m = memo[pos][ conversion[prev.a[0][0]] ][ conversion[prev.a[0][1]] ][ conversion[prev.a[1][0]] ][ conversion[prev.a[1][1]] ];
		if (m == -1)
			m = max(
			        F(pos + 1, give(pos, 0, prev)) + diff(pos, 0, prev),
			        F(pos + 1, give(pos, 1, prev)) + diff(pos, 1, prev)
			    );
		return m;
	}
}

int main() {
	ios_base::sync_with_stdio(0);
	cin.tie(0);
	memset(memo, -1, sizeof memo);
	conversion[0] = 0;
	conversion['M'] = 1;
	conversion['F'] = 2;
	conversion['B'] = 3;
	cin >> N >> shipment;
	cout << F(0, {{{0, 0}, {0, 0}}}) << '\n';
}

Compilation message (stderr)

miners.cpp: In function 'int diff(int, int, Prev)':
miners.cpp:25:27: warning: array subscript has type 'char' [-Wchar-subscripts]
  foodCount[prev.a[mine][0]]++;
                           ^
miners.cpp:26:27: warning: array subscript has type 'char' [-Wchar-subscripts]
  foodCount[prev.a[mine][1]]++;
                           ^
miners.cpp:27:25: warning: array subscript has type 'char' [-Wchar-subscripts]
  foodCount[shipment[pos]]++;
                         ^
miners.cpp: In function 'int F(int, Prev)':
miners.cpp:44:46: warning: array subscript has type 'char' [-Wchar-subscripts]
   int &m = memo[pos][ conversion[prev.a[0][0]] ][ conversion[prev.a[0][1]] ][ conversion[prev.a[1][0]] ][ conversion[prev.a[1][1]] ];
                                              ^
miners.cpp:44:74: warning: array subscript has type 'char' [-Wchar-subscripts]
   int &m = memo[pos][ conversion[prev.a[0][0]] ][ conversion[prev.a[0][1]] ][ conversion[prev.a[1][0]] ][ conversion[prev.a[1][1]] ];
                                                                          ^
miners.cpp:44:102: warning: array subscript has type 'char' [-Wchar-subscripts]
   int &m = memo[pos][ conversion[prev.a[0][0]] ][ conversion[prev.a[0][1]] ][ conversion[prev.a[1][0]] ][ conversion[prev.a[1][1]] ];
                                                                                                      ^
miners.cpp:44:130: warning: array subscript has type 'char' [-Wchar-subscripts]
   int &m = memo[pos][ conversion[prev.a[0][0]] ][ conversion[prev.a[0][1]] ][ conversion[prev.a[1][0]] ][ conversion[prev.a[1][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