Submission #955195

#	Time	Username	Problem	Language	Result	Execution time	Memory
955195		Otalp	Maze (JOI23_ho_t3)	C++14	43 / 100	2058 ms	177400 KiB

Main

#include<bits/stdc++.h>
using namespace std;
#define pb push_back
#define pii pair<int, int>
#define ff first
#define ss second


int n, m, k;
vector<vector<int> > a, dp, us;
struct node{
    int x=1e9;
    node *l=nullptr, *r=nullptr;
    node(){}
};


void dupd(node *v, int l, int r, int pos, int x){
    if(l == r){
        v -> x = min(x, v -> x);
        return;
    }
    int mid=(l+r)/2;
    if(mid >= pos){
        if(!v -> l) v -> l = new node();
        dupd(v -> l, l, mid, pos, x);
    }
    else{
        if(!v -> r) v -> r = new node();
        dupd(v -> r, mid + 1, r, pos, x);
    }
    v -> x = min((v->l ?v -> l -> x :(int)1e9), (v -> r ? v->r->x :(int)1e9));
}

int dget(node *v, int l, int r, int L, int R){
    if(v == nullptr) return 1e9;
    if(r < L or R < l){
        return 1e9;
    }
    if(L <= l and r <= R){
        return v -> x;
    }
    int mid=(l+r)/2;
    return min(dget(v -> l, l, mid, L, R), dget(v -> r, mid+1, r, L, R));
}

vector<node*> t;

void upd(int v, int l, int r, int L, int R, int x){
    dupd(t[v], 1, m, R, x);
    if(l == r){
        return;
    }
    int mid = (l + r)/2;
    if(mid >= L){
        upd(v+v, l, mid, L, R, x);
    }
    else{
        upd(v+v+1, mid+1, r, L, R, x); 
    }
}


int get(int v, int l, int r, int lx, int rx, int ly, int ry){
    if(rx < l or r < lx){
        return 1e9;
    }
    if(lx <= l and r <= rx){
        return dget(t[v], 1, m, ly, ry); 
    }
    int mid=(l+r)/2;
    return min(get(v+v, l, mid, lx, rx, ly, ry), get(v+v+1, mid+1, r, lx, rx, ly, ry));
}

void solve(){
    cin>>n>>m>>k;
    pii s, g;
    cin>>s.ff>>s.ss;
    cin>>g.ff>>g.ss;
    for(int i=0; i<=4 * n+100; i++){
        t.pb(new node());
    }
    for(int i=0; i<=n + 2; i++){
        us.pb({});
        dp.pb({});
        a.pb({});
        for(int j=0; j<=m + 2; j++){
            dp[i].pb(0);
            us[i].pb(0);
            a[i].pb(0);
        }
    }
    for(int i=1; i<=n; i++){
        for(int j=1; j<=m; j++){
            char c;
            cin>>c;
            if(c == '#') a[i][j] = 1;
            else a[i][j] = 0;
        }
    }
    vector<pii> nap = {{-1, 0}, {0, 1}, {1, 0}, {0, -1}};
    deque<pair<pii, int>> h;
    h.pb({s, 0});
    while(h.size()){
        int x=h[0].ff.ff, y=h[0].ff.ss;
        if(us[x][y]){
            h.pop_front();
            continue;
        }
        dp[x][y] = h[0].ss;
        us[x][y] = 1;
        upd(1, 1, n, x, y, dp[x][y]);
        h.pop_front();
        for(pii d: nap){
            if(!us[x + d.ff][y + d.ss] and x + d.ff <= n and x + d.ff >= 1 and y + d.ss <= m and y + d.ss >= 1){
                if(a[x + d.ff][y + d.ss] == 0) h.push_front({{x + d.ff, y + d.ss}, dp[x][y]});
                else{
                    if(dp[x][y] >= m / k + n / k + 2){
                        h.push_front({{x + d.ff, y + d.ff}, dp[x][y]});
                        continue;
                    }
                    int g = get(1, 1, n, max(1, x+d.ff-k), min(n, x+d.ff+k), max(1, y+d.ss-k+1), min(m, y+d.ss+k-1));
                    g = min(g, get(1, 1, n, max(1, x+d.ff-k+1), min(n, x+d.ff+k-1), max(1, y+d.ss-k), min(m, y+d.ss+k)));
                    if(g < dp[x][y]) h.push_front({{x + d.ff, y + d.ss}, g + 1});
                    else h.pb({{x + d.ff, y + d.ss}, g + 1});
                    //cout<<x<<' '<<y<<' '<<x+d.ff<<' '<<y + d.ss<<' '<<max(1, x+d.ff-k)<<' '<<min(n, x+d.ff+k)<<' '<<max(1, y+d.ss-k+1)<<' '<<min(m, y+d.ss+k-1)<<' '<<'\n';
                }
                continue;
            }
        }
    }
    for(int i=1; i<=n; i++){
        for(int j=1; j<=m; j++){
            //cout<<dp[i][j]<<' ';
        }
        //cout<<'\n';
    }
    cout<<dp[g.ff][g.ss];
}   


int main(){
    solve();
}

• Subtask 1: 0 / 8
• Subtask 2: 19 / 19
• Subtask 3: 0 / 16
• Subtask 4: 19 / 19
• Subtask 5: 5 / 5
• Subtask 6: 0 / 19
• Subtask 7: 0 / 8
• Subtask 8: 0 / 6