Submission #256331

#	Time	Username	Problem	Language	Result	Execution time	Memory
256331		shayan_p	Vim (BOI13_vim)	C++14	42.50 / 100	31 ms	3320 KiB

vim

// And you curse yourself for things you never done

#include<bits/stdc++.h>

#define F first
#define S second
#define PB push_back
#define sz(s) int((s).size())
#define bit(n,k) (((n)>>(k))&1)

using namespace std;

typedef long long ll;
typedef pair<int,int> pii;

const int maxn = 5010, mod = 1e9 + 7, inf = 1e9 + 10;

//int DP[maxn][maxn];

int nxt[maxn][10], lst[10];

map<pii, int> dp;
vector<int> poses;

int solve(int i, int j){
    if(i >= sz(poses))
	return 0;
    if(dp.count({i, j}))
	return dp[{i, j}];
    if(j >= poses[i])
	return dp[{i, j}] = j - poses[i] + solve( upper_bound(poses.begin(), poses.end(), j) - poses.begin(), poses[i] );
    int pt = lower_bound(nxt[j], nxt[j] + 10, poses[i]) - nxt[j];
    /*
    if(pt == 9)
	return dp[{i, j}] = 2 + solve(i, nxt[j][8]);
    int ans = 2 + solve(i, nxt[j][pt]);
    if(pt != 0 && nxt[j][pt-1] != j)
	ans = min(ans, 2 + solve(i, nxt[j][pt-1]) );
	return dp[{i, j}] = ans;*/
    int ans = inf;
    for(int w = 8 ; w >= 0 && nxt[j][w] != j && w >= pt-1; w--){
	ans = min(ans, 2 + solve(i, nxt[j][w]));
    }
    return dp[{i, j}] = ans;
}

int main(){
    ios_base::sync_with_stdio(false); cin.tie(0); cout.tie();

    int n;
    cin >> n;
    string _s, s;
    cin >> _s;
    int ans = 0;
    for(int i = 0; i < n; i++){
	if(_s[i] == 'e')
	    ans+= 2;
	if(_s[i] == 'e' && _s[i + 1] != 'e')
	    poses.PB(sz(s));
	if(_s[i] != 'e')
	    s+= _s[i];	
    }
    memset(lst, -1, sizeof lst);
    memset(nxt, -1, sizeof nxt);
    n = sz(s);
    for(int i = n-1; i >= 0; i--){
	for(int j = 0; j < 9; j++)
	    nxt[i][j] = (lst[j] == -1 ? i : lst[j]);
	sort(nxt[i], nxt[i] + 9);
	nxt[i][9] = inf;
	int id = (s[i] - 'a') - (s[i] > 'e');
	lst[id] = i;
    }
    /*    
    
    for(int i = sz(poses)-1; i >= 0; i--){
	int pt = sz(poses)-1;
	for(int j = n-1; j >= 0; j--){
	    DP[i][j] = inf;
	    if(pt >= i)
		DP[i][j] = j - poses[i] + DP[pt + 1][poses[i]];
	    for(int k = 0; k < 9; k++)
		if(nxt[j][k] != -1)
		    DP[i][j] = min(DP[i][j], 2 + DP[i][nxt[j][k]]);	    
	    if(poses[pt] == j)
		pt--;
	    if(DP[i][j] != solve(i, j))
		cout << "HHH " << " " << s[j-1] << s[j] << s[j+1] << " " << i << " " << j << " " << solve(i, j) << " " << DP[i][j] << endl;
	}
    }
    */
    ans+= solve(0, 0);
    return cout << ans << "\n", 0;
}

• Subtask 1: 37.5 / 50
• Subtask 2: 5 / 10
• Subtask 3: 0 / 40