Submission #364911

#	Time	Username	Problem	Language	Result	Execution time	Memory
364911		Sparky_09	Miners (IOI07_miners)	C++17	100 / 100	84 ms	1004 KiB

miners

#include "bits/stdc++.h"
using namespace std;
#define rep(i, a, b) for(int i = a; i < (b); ++i)
#define all(x) begin(x), end(x)
#define trav(a, x) for(auto& a : x)
#define sz(x) (int)(x).size()
typedef long long ll;
typedef pair<ll, ll> pii;
typedef vector<ll> vi;
typedef vector<pii> vpi;

void usaco(string s){
  freopen((s+".in").c_str(), "r", stdin);
  freopen((s+".out").c_str(), "w", stdout);
}

const int INF = 1e9;
int n, inp[100005], dp[2][4][4][4][4], ans = 0, pre[4][4][4];
string s;

int val(int x, int y, int z){
  set<int> temp; 
  if(x) temp.insert(x); 
  if(y) temp.insert(y); 
  if(z) temp.insert(z); 
  return sz(temp);
}

int main() {
	cin.tie(0)->sync_with_stdio(0);
	cin.exceptions(cin.failbit);
#ifdef LOCAL_DEFINE
	freopen("input.txt", "r", stdin);
#endif
  cin >> n >> s;
  rep(i, 1, n+1) inp[i] = (s[i-1] == 'B' ? 1 : (s[i-1] == 'M' ? 2 : 3));
  rep(i, 0, 2) rep(j, 0, 4) rep(k, 0, 4) rep(l, 0, 4) rep(m, 0, 4) dp[i][j][k][l][m] = -INF;
  rep(j, 0, 4) rep(k, 0, 4) rep(l, 0, 4) pre[j][k][l] = val(j,k,l);
  dp[0][0][0][0][0] = 0;
  rep(i, 1, n+1){
    int I = (i % 2 ? 1 : 0), c = inp[i];
    rep(j, 0, 4) rep(k, 0, 4) rep(l, 0, 4) rep(m, 0, 4){
      dp[I][j][k][m][c] = max(dp[I][j][k][m][c], dp[I^1][j][k][l][m] + pre[m][l][c]);
      dp[I][k][c][l][m] = max(dp[I][k][c][l][m], dp[I^1][j][k][l][m] + pre[j][k][c]);
      if(i == n) ans = max({ans, dp[I][k][c][l][m], dp[I][j][k][m][c]});
    }
  }
  cout << ans << '\n';
}

Compilation message (stderr)

miners.cpp: In function 'void usaco(std::string)':
miners.cpp:13:10: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)', declared with attribute warn_unused_result [-Wunused-result]
   13 |   freopen((s+".in").c_str(), "r", stdin);
      |   ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
miners.cpp:14:10: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)', declared with attribute warn_unused_result [-Wunused-result]
   14 |   freopen((s+".out").c_str(), "w", stdout);
      |   ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

• 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