Submission #94009

#	Time	Username	Problem	Language	Result	Execution time	Memory
94009		tincamatei	Miners (IOI07_miners)	C++14	100 / 100	199 ms	100872 KiB

miners

#include <bits/stdc++.h>

using namespace std;

const int MAX_N = 100000;
const int INF = 1<<30;

string str;
int dp[1+MAX_N][4][4][4][4];

int conv(char x) {
  if(x == 'M')
    return 1;
  if(x == 'B')
    return 2;
  return 3;
}

int cost(int a, int b, int c) {
  if(a == 0 && b == 0)
    return 1;
  if(a == 0)
    return 1 + (b != c);
  if(a == b && b == c)
    return 1;
  else if(a != b && a != c && b != c)
    return 3;
  return 2;
}

int main() {
  int n;
  cin >> n >> str;

  for(int i = 0; i <= n; ++i)
    for(int a1 = 0; a1 < 4; ++a1)
    for(int b1 = 0; b1 < 4; ++b1)
    for(int a2 = 0; a2 < 4; ++a2)
    for(int b2 = 0; b2 < 4; ++b2)
      dp[i][a1][b1][a2][b2] = -INF;
  dp[0][0][0][0][0] = 0;

  for(int i = 0; i < n; ++i) {
    int c = conv(str[i]);
    for(int a1 = 0; a1 < 4; ++a1)
    for(int b1 = 0; b1 < 4; ++b1)
    for(int a2 = 0; a2 < 4; ++a2)
    for(int b2 = 0; b2 < 4; ++b2) {
      dp[i + 1][a1][b1][b2][c] = max(dp[i + 1][a1][b1][b2][c],
                                     dp[i][a1][b1][a2][b2] + cost(a2, b2, c));
      dp[i + 1][b1][c][a2][b2] = max(dp[i + 1][b1][c][a2][b2],
                                     dp[i][a1][b1][a2][b2] + cost(a1, b1, c));
    }
  }

  int rez = -INF;
  for(int a1 = 0; a1 < 4; ++a1)
  for(int b1 = 0; b1 < 4; ++b1)
  for(int a2 = 0; a2 < 4; ++a2)
  for(int b2 = 0; b2 < 4; ++b2)
    rez = max(rez, dp[n][a1][b1][a2][b2]);

  cout << rez;
  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