Submission #818927

#	Time	Username	Problem	Language	Result	Execution time	Memory
818927		vjudge1	Growing Vegetable is Fun 3 (JOI19_ho_t3)	C++17	5 / 100	1088 ms	162184 KiB

joi2019_ho_t3

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

typedef long long ll;
const ll MAXN = 1e5 + 5;
const ll INF = 1e9;
#define fi first
#define se second

ll n;
string s;
map <string, bool> vis;
queue <pair <ll, string> > q;

bool cek(string x){
    for(ll i = 0; i < n-1; i++){
        if(x[i] == x[i+1]){
            return false;
        }
    }
    return true;
}

void bfs(string x){
    vis[x] = true;
    q.push({0, x});
    while(!q.empty()){
        ll discur = q.front().fi;
        string cur = q.front().se;
        // cout << cur << " " << discur << endl;
        q.pop();
        if(cek(cur)){
            cout << discur << endl;
            exit(0);
        }
        for(ll i = 0; i < n-1; i++){
            if(((i-1 >= 0 && cur[i] == cur[i-1]) || (i+2 <n && cur[i+1] == cur[i+2])) && cur[i] != cur[i+1]){
                swap(cur[i], cur[i+1]);
                if(!vis[cur]){
                    vis[cur] = true;
                    q.push({discur+1, cur});
                }
                swap(cur[i], cur[i+1]);
            }
        }
    }
    cout << -1 << endl;
    return;
}

int main(){
    ios_base::sync_with_stdio(0); cin.tie(0); cout.tie(0);
    cin >> n >> s;
    bfs(s);
}

• Subtask 1: 5 / 5
• Subtask 2: 0 / 55
• Subtask 3: 0 / 15
• Subtask 4: 0 / 25