Submission #588641

#	Time	Username	Problem	Language	Result	Execution time	Memory
588641		wiwiho	Virus Experiment (JOI19_virus)	C++14	100 / 100	268 ms	19156 KiB

virus

#include <bits/stdc++.h>
#include <bits/extc++.h>

#define StarBurstStream ios_base::sync_with_stdio(false); cin.tie(0); cout.tie(0);
#define iter(a) a.begin(), a.end()
#define riter(a) a.rbegin(), a.rend()
#define lsort(a) sort(iter(a))
#define gsort(a) sort(riter(a))
#define pb(a) push_back(a)
#define eb(a) emplace_back(a)
#define pf(a) push_front(a)
#define ef(a) emplace_front(a)
#define pob pop_back()
#define pof pop_front()
#define mp(a, b) make_pair(a, b)
#define F first
#define S second
#define mt make_tuple
#define gt(t, i) get<i>(t)
#define tomax(a, b) ((a) = max((a), (b)))
#define tomin(a, b) ((a) = min((a), (b)))
#define topos(a) ((a) = (((a) % MOD + MOD) % MOD))
#define uni(a) a.resize(unique(iter(a)) - a.begin())
#define printv(a, b) {bool pvaspace=false; \
for(auto pva : a){ \
    if(pvaspace) b << " "; pvaspace=true;\
    b << pva;\
}\
b << "\n";}

using namespace std;
using namespace __gnu_pbds;

typedef long long ll;
typedef unsigned long long ull;
typedef long double ld;

using pii = pair<int, int>;
using pll = pair<ll, ll>;
using pdd = pair<ld, ld>;
using tiii = tuple<int, int, int>;

const ll MOD = 1000000007;
const ll MAX = 2147483647;

template<typename A, typename B>
ostream& operator<<(ostream& o, pair<A, B> p){
    return o << '(' << p.F << ',' << p.S << ')';
}

ll ifloor(ll a, ll b){
    if(b < 0) a *= -1, b *= -1;
    if(a < 0) return (a - b + 1) / b;
    else return a / b;
}

ll iceil(ll a, ll b){
    if(b < 0) a *= -1, b *= -1;
    if(a > 0) return (a + b - 1) / b;
    else return a / b;
}

int R, C;
int n, m;
vector<vector<int>> u;
vector<int> dsu, sz;
vector<int> lst;
vector<int> ans;
vector<int> lim;
vector<vector<int>> vst;
int tme = 0, ts = 0;
int mnans = INT_MAX;

vector<char> cs = {'N', 'S', 'W', 'E'};
vector<pii> dir = {mp(-1, 0), mp(1, 0), mp(0, -1), mp(0, 1)};
vector<int> cid;

void init(){
    n = R * C;
    u.resize(R, vector<int>(C));
    dsu.resize(n);
    sz.resize(n, 1);
    iota(iter(dsu), 0);
    lst.resize(n);
    ans.resize(n, -1);
    lim.resize(16);
    cid.resize(26);
    vst.resize(R, vector<int>(C));
    for(int i = 0; i < 4; i++) cid[cs[i] - 'A'] = i;
}

int findDSU(int a){
    if(dsu[a] != a) dsu[a] = findDSU(dsu[a]);
    return dsu[a];
}

void unionDSU(int a, int b){
    a = findDSU(a);
    b = findDSU(b);
    if(a == b) return;
    //cerr << "union " << a / C << ',' << a % C << " " << b / C << ',' << b % C << " " << tme << "\n";
    dsu[b] = dsu[a];
    sz[a] += sz[b];
    lst[a] = tme;
}

int getid(int x, int y){
    if(x < 0 || R <= x || y < 0 || C <= y) return -1;
    return x * C + y;
}

bool check(int x, int y){
    if(u[x][y] == 0) return false;
    int tmp = 0;
    for(int i = 0; i < 4; i++){
        int nx = x + dir[i].F, ny = y + dir[i].S;
        int id = getid(nx, ny);
        if(id == -1) continue;
        if(vst[nx][ny] == ts) tmp |= 1 << i;
    }
    return lim[tmp] >= u[x][y];
}

bool bfs(int sx, int sy){
    ts++;
    bool ok = false;
    int cnt = 0;
    int sid = getid(sx, sy);
    queue<pii> q;
    vst[sx][sy] = ts;
    q.push(mp(sx, sy));
    while(!q.empty()){
        int x = q.front().F, y = q.front().S;
        q.pop();
        int id = getid(x, y);
        cnt++;
        if(findDSU(sid) != findDSU(id)){
            unionDSU(id, sid);
            ok = true;
            break;
        }
        for(auto [dx, dy] : dir){
            int nx = x + dx, ny = y + dy;
            int nid = getid(nx, ny);
            if(nid == -1) continue;
            if(vst[nx][ny] == ts) continue;
            if(!check(nx, ny)) continue;
            vst[nx][ny] = ts;
            q.push(mp(nx, ny));
        }
    }
    if(!ok){
        ans[findDSU(sid)] = cnt;
        //cerr << "ans " << sx << " " << sy << " : " << cnt << "\n";
        if(cnt < mnans){
            mnans = cnt;
        }
    }
    return ok;
}

int main(){
    StarBurstStream

    cin >> m >> R >> C;
    string s;
    cin >> s;
    for(int i = 0; i < m; i++) s += s[i];
    init();
    for(int i = 0; i < R; i++){
        for(int j = 0; j < C; j++) cin >> u[i][j];
    }
    
    for(int i = 0; i < 16; i++){
        int now = 0;
        int mx = 0;
        for(int j = 0; j < 2 * m; j++){
            int id = cid[s[j] - 'A'];
            if(!(1 << id & i)){
                now = 0;
                continue;
            }
            now++;
            mx = max(mx, now);
        }
        if(mx == 2 * m) mx = MAX;
        lim[i] = mx;
        //cerr << bitset<4>(i) << ": " << lim[i] << "\n";
    }

    while(true){
        tme++;
        //cerr << "round " << tme << "\n";
        bool ok = false;
        for(int i = 0; i < R; i++){
            for(int j = 0; j < C; j++){
                if(u[i][j] == 0) continue;
                int id = getid(i, j);
                if(id != findDSU(id)) continue;
                if(ans[id] != -1) continue;
                if(lst[id] == tme) continue;
                //cerr << "check " << i << " " << j << " " << lst[id] << " " << tme << "\n";
                if(bfs(i, j)) ok = true;
            }
        }
        //cerr << "map:\n";
        for(int i = 0; i < R; i++){
            for(int j = 0; j < C; j++){
                int t = findDSU(getid(i, j));
                //cerr << t / C << "," << t % C << " ";
            }
            //cerr << "\n";
        }
        if(!ok) break;
    }

    int anscnt = 0;
    
    for(int i = 0; i < R; i++){
        for(int j = 0; j < C; j++){
            int id = getid(i, j);
            if(findDSU(id) != id) continue;
            if(ans[id] != mnans) continue;
            anscnt += min(mnans, sz[id]);
        }
    }

    cout << mnans << "\n" << anscnt << "\n";

    return 0;
}

Compilation message (stderr)

virus.cpp: In function 'bool bfs(int, int)':
virus.cpp:142:18: warning: structured bindings only available with '-std=c++17' or '-std=gnu++17'
  142 |         for(auto [dx, dy] : dir){
      |                  ^
virus.cpp: In function 'int main()':
virus.cpp:209:21: warning: unused variable 't' [-Wunused-variable]
  209 |                 int t = findDSU(getid(i, j));
      |                     ^

• Subtask 1: 14 / 14
• Subtask 2: 6 / 6
• Subtask 3: 80 / 80