Submission #1117401

#	Time	Username	Problem	Language	Result	Execution time	Memory
1117401		icebear	Miners (IOI07_miners)	C++17	100 / 100	169 ms	201196 KiB

miners

// ~~ icebear love atttttttttttt ~~
#include <bits/stdc++.h>
using namespace std;

typedef long long ll;
typedef pair<int, int> ii;
typedef pair<ii, int> iii;

#define FOR(i,a,b) for(int i=(a); i<=(b); ++i)
#define FORR(i,a,b) for(int i=(a); i>=(b); --i)
#define rep(i, n) for(int i=0; i<(n); ++i)
#define red(i, n) for(int i=(n)-1; i>=0; --i)
#define mp make_pair
#define pb push_back
#define fi first
#define se second
#define all(x) x.begin(), x.end()
#define task "miners"

const int MOD = 1e9 + 7;
const int inf = 1e9 + 27092008;
const ll LLinf = 1e18 + 27092008;
const int N = 2e5 + 5;
int n, a[N];
int dp[N][4][4][4][4];

void maximize(int &x, int y) {x = max(x, y);}

void solve() {
	cin >> n;
	FOR(i, 1, n) {
		char c;
		cin >> c;
		if (c == 'M') a[i] = 1;
		if (c == 'F') a[i] = 2;
		if (c == 'B') a[i] = 3;
	}
	memset(dp, -0x3f, sizeof dp);
	int INF = -dp[0][0][0][0][0], res = 0;
	dp[0][0][0][0][0] = 0;

	FOR(i, 0, n + 1) FOR(a1, 0, 3) FOR(a2, 0, 3) FOR(b1, 0, 3) FOR(b2, 0, 3) 
		if (dp[i][a1][a2][b1][b2] != -INF) {
			maximize(res, dp[i][a1][a2][b1][b2]);
			int cnt = 1;

			if (a[i] != a1 && a1 != 0) cnt++;
			if (a[i] != a2 && a1 != a2 && a1 != 0 && a2 != 0) cnt++;
			maximize(dp[i + 1][a[i]][a1][b1][b2], dp[i][a1][a2][b1][b2] + cnt);

			cnt = 1;
			if (a[i] != b1 && b1 != 0) cnt++;
			if (a[i] != b2 && b1 != b2 && b2 != 0 && b1 != 0) cnt++;	 
			maximize(dp[i + 1][a1][a2][a[i]][b1], dp[i][a1][a2][b1][b2] + cnt);
		}
	cout << res-1;
}

int main() {
	ios_base::sync_with_stdio(0);
	cin.tie(0); cout.tie(0);
	if (fopen(task".inp", "r")){
		freopen(task".inp", "r", stdin);
		freopen(task".out", "w", stdout);
	}
	int tc = 1;
//     cin >> tc;
	while(tc--) solve();
	return 0;
}

Compilation message (stderr)

miners.cpp: In function 'int main()':
miners.cpp:63:10: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
   63 |   freopen(task".inp", "r", stdin);
      |   ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~
miners.cpp:64:10: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
   64 |   freopen(task".out", "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