Submission #860448

#	Time	Username	Problem	Language	Result	Execution time	Memory
860448		meliodasssf	Bajka (COCI20_bajka)	C++17	50 / 70	7 ms	6748 KiB

bajka

#include <bits/stdc++.h> //hi
using namespace std;

#define endl '\n'

int n,m;
int A[100010],B[100010];
int L[100010],R[100010];

void in()
{
    cin >> n >> m;
    for (int i=1; i<=n; i++)
    {
        char x;
        cin >> x;
        A[i] = x - 'a' + 1;
    }
    for (int i=1; i<=n; i++)
    {
        char x;
        cin >> x;
        B[i] = x - 'a' + 1;
    }
    // for (int i=1; i<=n; i++) cout << A[i] << ' ' ; cout << endl;
    // for (int i=1; i<=n; i++) cout << B[i] << ' ' ; cout << endl;
}

void set_up()
{
    int tmp[100];
    memset(tmp,-1,sizeof(tmp));
    for (int i=1; i<=n; i++)
    {
        if (tmp[A[i]] != -1) L[i] = tmp[A[i]];
        tmp[A[i]] = i;
    }
    memset(tmp,-1,sizeof(tmp));
    for (int i=n; i>=1; i--)
    {
        if (tmp[A[i]] != -1) R[i] = tmp[A[i]];
        tmp[A[i]] = i;
    }
    // for (int i=1; i<=n; i++) cout << L[i] << ' ' ; cout << endl;
    // for (int i=1; i<=n; i++) cout << R[i] << ' ' ; cout << endl;
}

long long dp[1010][1010];
bool visited[1010][1010];
 
struct State
{
    int pref;
    int pos;
};
 
struct Path
{
    State s;
    long long len;
};
 
bool operator < (const Path &a, const Path &b)
{
    return a.len > b.len;
}
 
void dijkstra()
{
    priority_queue <Path> pq;
    for(int i = 1; i <= n; i++)
        if(A[i] == B[1])
            pq.push(Path{State{1, i}, 0});
    while(pq.empty() == false)
    {
        Path p = pq.top();
        pq.pop();
        if(visited[p.s.pref][p.s.pos] == true)
            continue;
        visited[p.s.pref][p.s.pos] = true;
        dp[p.s.pref][p.s.pos] = p.len;
        if(p.s.pref == m)
            continue;
        if(p.s.pos > 1 && A[p.s.pos - 1] == B[p.s.pref + 1] && visited[p.s.pref + 1][p.s.pos - 1] == false)
            pq.push(Path{State{p.s.pref + 1, p.s.pos - 1}, p.len + 1});
        if(p.s.pos < n && A[p.s.pos + 1] == B[p.s.pref + 1] && visited[p.s.pref + 1][p.s.pos + 1] == false)
            pq.push(Path{State{p.s.pref + 1, p.s.pos + 1}, p.len + 1});
        int pos1 = L[p.s.pos];
        int pos2 = R[p.s.pos];
        if(pos1 != 0 && visited[p.s.pref][pos1] == false)
            pq.push(Path{State{p.s.pref, pos1}, p.len + abs(p.s.pos - pos1)});
        if(pos2 != 0 && visited[p.s.pref][pos2] == false)
            pq.push(Path{State{p.s.pref, pos2}, p.len + abs(p.s.pos - pos2)});
    }
}

signed main()
{
    ios_base::sync_with_stdio(0); cin.tie(0);
    in();
    set_up();

    dijkstra();
    long long res = LLONG_MAX;
    for (int i=1; i<=n; i++)
    {
        if(visited[m][i] == true)
        {
            res = min(res, dp[m][i]);
        }
    }

    if(res == LLONG_MAX) cout << -1;
    else cout << res;
    return 0;
}

• Subtask 1: 0 / 20
• Subtask 2: 50 / 50