oj.uz

Submission #594142

# Submission time Handle Problem Language Result Execution time Memory
594142 2022-07-12T06:57:04 Z 박상훈(#8431) None (JOI16_ho_t4) C++17
100 / 100
 95 ms 11480 KB 
#include <bits/stdc++.h>

typedef long long ll;
using namespace std;
int n, k, dx[4] = {1, 0, -1, 0}, dy[4] = {0, -1, 0, 1}, cc[1234];
char s[100100];
map<pair<ll, ll>, vector<pair<ll, ll>>> M;
ll a, b, d, ans;

ll myabs(ll x){
    if (x<0) return -x;
    return x;
}

pair<ll, ll> _convert(ll x, ll y){
    ll s = ((x+b*(int)1e9)%b)/(b/d)%d;
    return {a*x+b*y, s};
}


ll fx = 0, fy = 0;
void simulate(bool flag){

    if (flag) M[_convert(0, 0)].emplace_back(fx, fx+(ll)k*b);

    for (int i=1;i<=n;i++){
        fx += dx[cc[s[i]]], fy += dy[cc[s[i]]];

        if (flag){
            auto p = _convert(fx, fy);
            M[p].emplace_back(fx, fx + (ll)k*b);
        }

        //if (flag)printf(" %lld %lld\n", fx, fy);
    }
}

void compress(vector<pair<ll, ll>> &V){
    vector<pair<ll, ll>> ret;
    sort(V.begin(), V.end());

    for (auto &[s, e]:V){
        if (ret.empty()) {ret.emplace_back(s, e); continue;}

        if (ret.back().second>=s) ret.back().second = e;
        else ret.emplace_back(s, e);
    }
    swap(V, ret);
}

void init(){
    cc['E'] = 0, cc['S'] = 1, cc['W'] = 2, cc['N'] = 3;
    simulate(0);
    if (fx==0 && fy==0) {fx = 1; k = 1;}

    else if (fx==0){
        cc['E'] = 3, cc['N'] = 0;
        cc['S'] = 2, cc['W'] = 1;
        fx = 0, fy = 0;
        simulate(0);
        assert(fx);
    }

    if (fx<0){
        if (cc['E'] == 0) swap(cc['E'], cc['W']);
        else swap(cc['S'], cc['N']);
        fx = 0, fy = 0;
        simulate(0);
        assert(fx>0);
    }

    d = myabs(__gcd(fx, fy));
    a = -fy, b = fx;
    fx = 0, fy = 0;

    //printf(" a = %lld, b = %lld, d = %lld\n", a, b, d);

    simulate(1);
    for (auto &[p, V]:M) compress(V);

    //printf("Init ok\n");
}

void get_event(vector<pair<ll, int>> &Event, vector<pair<ll, ll>> &V, int ofs){
    for (auto &[s, e]:V){
        Event.emplace_back(s+ofs, 1);
        Event.emplace_back(e+ofs, -1);
    }
}

bool valid(ll x, ll y){
    if (M.find(_convert(x, y+1))==M.end()) return 0;
    if (M.find(_convert(x+1, y))==M.end()) return 0;
    if (M.find(_convert(x+1, y+1))==M.end()) return 0;
    return 1;
}

void solve(){
    for (auto &[p, V]:M){
        //printf(" %lld: %d\n", p.first, (int)V.size());
        ll x = V[0].first;
        ll y = (p.first - x*a) / b;

        if (!valid(x, y)) continue;
        //printf("YES: %lld %lld\n", x, y);

        vector<pair<ll, int>> Event;
        get_event(Event, V, 0);
        get_event(Event, M[_convert(x, y+1)], 0);
        get_event(Event, M[_convert(x+1, y)], -1);
        get_event(Event, M[_convert(x+1, y+1)], -1);

        sort(Event.begin(), Event.end());
        //for (auto [t, i]:Event) printf("  %lld -> %d\n", t, i);

        int cnt = 0;
        for (int i=0;i<(int)Event.size();){
            int r = i;
            for (;r<(int)Event.size();r++){
                if (Event[i].first!=Event[r].first) break;
                cnt += Event[r].second;
            }

            assert(cnt>=0 && cnt<=4);
            if (cnt==4){
                assert(r<(int)Event.size());
                ans += (Event[r].first - Event[i].first) / b;
            }

            assert(i<r);
            i = r;
        }
        //printf(" ok %lld\n", ans);
    }
}

mt19937 seed(129438);
uniform_int_distribution<int> rng(0, 2147483647);
int getrand(int l, int r){return rng(seed)%(r-l+1) + l;}

namespace NAIVE{

set<pair<int, int>> visited, made;
int dx[4] = {1, 0, -1, 0}, dy[4] = {0, -1, 0, 1}, cc[1234];
char s[100100];

bool ok(int x, int y){
    return visited.find(make_pair(x, y))!=visited.end();
}

int _make(int x, int y){
    if (made.find(make_pair(x, y))!=made.end()) return 0;
    if (ok(x, y) && ok(x+1, y) && ok(x, y+1) && ok(x+1, y+1)){
        made.emplace(x, y);
        return 1;
    }
    return 0;
}

ll solve(int n, int k, char t[]){
    visited.clear();
    made.clear();

    for (int i=1;i<=n;i++) s[i] = t[i];
    s[n+1] = 0;

    cc['E'] = 0, cc['S'] = 1, cc['W'] = 2, cc['N'] = 3;

    int prv = 1e9, x = 0, y = 0, c = 0;
    ll ans = 0;

    visited.emplace(0, 0);
    while(k){
        int cnt = 0;
        for (int i=1;i<=n;i++){
            x += dx[cc[s[i]]], y += dy[cc[s[i]]];
            visited.emplace(x, y);
            cnt += _make(x, y);
            cnt += _make(x, y-1);
            cnt += _make(x-1, y);
            cnt += _make(x-1, y-1);
        }
        ans += cnt;
        --k;
        ++c;
        if (c>100) break;
        //if (prv==cnt) break;
        prv = cnt;
        //printf("%d\n", cnt);
    }

    ans += (ll)prv * k;
    return ans;
    return 0;
}

}



ll solve(int N, int K, char t[]){
    n = N, k = K;
    fx = 0, fy = 0;
    a = 0, b = 0, d = 0, ans = 0;
    M.clear();


    for (int i=1;i<=n;i++) s[i] = t[i];
    s[n+1] = 0;
    /*for (int i=1;i<=n;i++){
        char t[10] = "xESWN";
        s[i] = t[getrand(1, 4)];
        printf("%c", s[i]);
    }
    printf("\n");*/

    init();

    solve();

    return ans;
}

char t[100100];
const int MAXN = 20, MAXK = 50;
void stress(int tc){
    printf("----------------------\n");
    printf("Stress #%d\n", tc);
    int N = getrand(1, MAXN), K = getrand(1, MAXK);
    for (int i=1;i<=N;i++){
        char T[10] = "xESWN";
        t[i] = T[getrand(1, 4)];
    }
    t[N+1] = 0;
    printf("Input:\n");
    printf("%d %d\n", N, K);
    printf("%s\n", t+1);

    ll ans = NAIVE::solve(N, K, t);
    ll out = solve(N, K, t);

    printf("answer: %lld\n", ans);
    printf("output: %lld\n", out);
    assert(ans==out);
}

int main(){
    int tc = 0;
    //scanf("%d", &tc);
    if (true){
        int n, k;
        scanf("%d %d", &n, &k);
        scanf("%s", t+1);
        printf("%lld\n", solve(n, k, t));
        //printf(" ans = %lld\n", NAIVE::solve(n, k, t));
    }
    for (int i=1;i<=tc;i++) stress(i);
}

Compilation message

2016_ho_t4.cpp: In function 'void simulate(bool)':
2016_ho_t4.cpp:27:24: warning: array subscript has type 'char' [-Wchar-subscripts]
   27 |         fx += dx[cc[s[i]]], fy += dy[cc[s[i]]];
      |                     ~~~^
2016_ho_t4.cpp:27:44: warning: array subscript has type 'char' [-Wchar-subscripts]
   27 |         fx += dx[cc[s[i]]], fy += dy[cc[s[i]]];
      |                                         ~~~^
2016_ho_t4.cpp: In function 'll NAIVE::solve(int, int, char*)':
2016_ho_t4.cpp:176:27: warning: array subscript has type 'char' [-Wchar-subscripts]
  176 |             x += dx[cc[s[i]]], y += dy[cc[s[i]]];
      |                        ~~~^
2016_ho_t4.cpp:176:46: warning: array subscript has type 'char' [-Wchar-subscripts]
  176 |             x += dx[cc[s[i]]], y += dy[cc[s[i]]];
      |                                           ~~~^
2016_ho_t4.cpp: In function 'int main()':
2016_ho_t4.cpp:252:14: warning: ignoring return value of 'int scanf(const char*, ...)' declared with attribute 'warn_unused_result' [-Wunused-result]
  252 |         scanf("%d %d", &n, &k);
      |         ~~~~~^~~~~~~~~~~~~~~~~
2016_ho_t4.cpp:253:14: warning: ignoring return value of 'int scanf(const char*, ...)' declared with attribute 'warn_unused_result' [-Wunused-result]
  253 |         scanf("%s", t+1);
      |         ~~~~~^~~~~~~~~~~

Subtask #1
5.0 / 5.0

# Verdict Execution time Memory Grader output
1 Correct 0 ms 212 KB Output is correct
2 Correct 1 ms 212 KB Output is correct
3 Correct 0 ms 212 KB Output is correct
4 Correct 0 ms 212 KB Output is correct
5 Correct 1 ms 212 KB Output is correct
6 Correct 0 ms 212 KB Output is correct
7 Correct 1 ms 232 KB Output is correct
8 Correct 1 ms 212 KB Output is correct
9 Correct 1 ms 212 KB Output is correct
10 Correct 0 ms 212 KB Output is correct
11 Correct 0 ms 212 KB Output is correct
12 Correct 0 ms 212 KB Output is correct
13 Correct 0 ms 212 KB Output is correct
14 Correct 0 ms 212 KB Output is correct
15 Correct 0 ms 212 KB Output is correct
16 Correct 0 ms 212 KB Output is correct
17 Correct 0 ms 212 KB Output is correct
18 Correct 0 ms 212 KB Output is correct
19 Correct 0 ms 212 KB Output is correct
20 Correct 0 ms 212 KB Output is correct
21 Correct 0 ms 212 KB Output is correct
22 Correct 0 ms 212 KB Output is correct
23 Correct 1 ms 212 KB Output is correct
24 Correct 0 ms 212 KB Output is correct
25 Correct 1 ms 212 KB Output is correct

Subtask #2
10.0 / 10.0

# Verdict Execution time Memory Grader output
1 Correct 0 ms 212 KB Output is correct
2 Correct 1 ms 212 KB Output is correct
3 Correct 0 ms 212 KB Output is correct
4 Correct 0 ms 212 KB Output is correct
5 Correct 1 ms 212 KB Output is correct
6 Correct 0 ms 212 KB Output is correct
7 Correct 1 ms 232 KB Output is correct
8 Correct 1 ms 212 KB Output is correct
9 Correct 1 ms 212 KB Output is correct
10 Correct 0 ms 212 KB Output is correct
11 Correct 0 ms 212 KB Output is correct
12 Correct 0 ms 212 KB Output is correct
13 Correct 0 ms 212 KB Output is correct
14 Correct 0 ms 212 KB Output is correct
15 Correct 0 ms 212 KB Output is correct
16 Correct 0 ms 212 KB Output is correct
17 Correct 0 ms 212 KB Output is correct
18 Correct 0 ms 212 KB Output is correct
19 Correct 0 ms 212 KB Output is correct
20 Correct 0 ms 212 KB Output is correct
21 Correct 0 ms 212 KB Output is correct
22 Correct 0 ms 212 KB Output is correct
23 Correct 1 ms 212 KB Output is correct
24 Correct 0 ms 212 KB Output is correct
25 Correct 1 ms 212 KB Output is correct
26 Correct 0 ms 212 KB Output is correct
27 Correct 2 ms 468 KB Output is correct
28 Correct 2 ms 724 KB Output is correct
29 Correct 17 ms 2644 KB Output is correct
30 Correct 17 ms 3092 KB Output is correct
31 Correct 38 ms 9812 KB Output is correct
32 Correct 10 ms 2684 KB Output is correct
33 Correct 37 ms 4748 KB Output is correct
34 Correct 39 ms 4832 KB Output is correct
35 Correct 31 ms 4600 KB Output is correct
36 Correct 24 ms 3856 KB Output is correct
37 Correct 11 ms 2900 KB Output is correct
38 Correct 30 ms 4488 KB Output is correct
39 Correct 31 ms 4644 KB Output is correct
40 Correct 9 ms 2900 KB Output is correct
41 Correct 23 ms 3284 KB Output is correct
42 Correct 27 ms 3796 KB Output is correct
43 Correct 33 ms 4572 KB Output is correct
44 Correct 33 ms 4556 KB Output is correct
45 Correct 27 ms 4268 KB Output is correct
46 Correct 37 ms 5204 KB Output is correct
47 Correct 56 ms 8316 KB Output is correct
48 Correct 6 ms 2760 KB Output is correct
49 Correct 63 ms 11408 KB Output is correct
50 Correct 49 ms 11348 KB Output is correct

Subtask #3
23.0 / 23.0

# Verdict Execution time Memory Grader output
1 Correct 0 ms 212 KB Output is correct
2 Correct 1 ms 212 KB Output is correct
3 Correct 0 ms 212 KB Output is correct
4 Correct 0 ms 212 KB Output is correct
5 Correct 1 ms 212 KB Output is correct
6 Correct 0 ms 212 KB Output is correct
7 Correct 1 ms 232 KB Output is correct
8 Correct 1 ms 212 KB Output is correct
9 Correct 1 ms 212 KB Output is correct
10 Correct 0 ms 212 KB Output is correct
11 Correct 0 ms 212 KB Output is correct
12 Correct 0 ms 212 KB Output is correct
13 Correct 0 ms 212 KB Output is correct
14 Correct 0 ms 212 KB Output is correct
15 Correct 0 ms 212 KB Output is correct
16 Correct 0 ms 212 KB Output is correct
17 Correct 0 ms 212 KB Output is correct
18 Correct 0 ms 212 KB Output is correct
19 Correct 0 ms 212 KB Output is correct
20 Correct 0 ms 212 KB Output is correct
21 Correct 0 ms 212 KB Output is correct
22 Correct 0 ms 212 KB Output is correct
23 Correct 1 ms 212 KB Output is correct
24 Correct 0 ms 212 KB Output is correct
25 Correct 1 ms 212 KB Output is correct
26 Correct 0 ms 212 KB Output is correct
27 Correct 0 ms 212 KB Output is correct
28 Correct 0 ms 212 KB Output is correct
29 Correct 0 ms 212 KB Output is correct
30 Correct 1 ms 212 KB Output is correct
31 Correct 0 ms 212 KB Output is correct
32 Correct 0 ms 212 KB Output is correct
33 Correct 0 ms 212 KB Output is correct
34 Correct 0 ms 212 KB Output is correct
35 Correct 0 ms 212 KB Output is correct
36 Correct 0 ms 212 KB Output is correct
37 Correct 0 ms 212 KB Output is correct
38 Correct 0 ms 212 KB Output is correct
39 Correct 0 ms 212 KB Output is correct
40 Correct 1 ms 212 KB Output is correct
41 Correct 0 ms 212 KB Output is correct
42 Correct 0 ms 212 KB Output is correct
43 Correct 0 ms 212 KB Output is correct
44 Correct 1 ms 212 KB Output is correct
45 Correct 1 ms 212 KB Output is correct
46 Correct 1 ms 212 KB Output is correct
47 Correct 0 ms 212 KB Output is correct
48 Correct 1 ms 212 KB Output is correct
49 Correct 0 ms 212 KB Output is correct
50 Correct 0 ms 212 KB Output is correct

Subtask #4
62.0 / 62.0

# Verdict Execution time Memory Grader output
1 Correct 0 ms 212 KB Output is correct
2 Correct 1 ms 212 KB Output is correct
3 Correct 0 ms 212 KB Output is correct
4 Correct 0 ms 212 KB Output is correct
5 Correct 1 ms 212 KB Output is correct
6 Correct 0 ms 212 KB Output is correct
7 Correct 1 ms 232 KB Output is correct
8 Correct 1 ms 212 KB Output is correct
9 Correct 1 ms 212 KB Output is correct
10 Correct 0 ms 212 KB Output is correct
11 Correct 0 ms 212 KB Output is correct
12 Correct 0 ms 212 KB Output is correct
13 Correct 0 ms 212 KB Output is correct
14 Correct 0 ms 212 KB Output is correct
15 Correct 0 ms 212 KB Output is correct
16 Correct 0 ms 212 KB Output is correct
17 Correct 0 ms 212 KB Output is correct
18 Correct 0 ms 212 KB Output is correct
19 Correct 0 ms 212 KB Output is correct
20 Correct 0 ms 212 KB Output is correct
21 Correct 0 ms 212 KB Output is correct
22 Correct 0 ms 212 KB Output is correct
23 Correct 1 ms 212 KB Output is correct
24 Correct 0 ms 212 KB Output is correct
25 Correct 1 ms 212 KB Output is correct
26 Correct 0 ms 212 KB Output is correct
27 Correct 2 ms 468 KB Output is correct
28 Correct 2 ms 724 KB Output is correct
29 Correct 17 ms 2644 KB Output is correct
30 Correct 17 ms 3092 KB Output is correct
31 Correct 38 ms 9812 KB Output is correct
32 Correct 10 ms 2684 KB Output is correct
33 Correct 37 ms 4748 KB Output is correct
34 Correct 39 ms 4832 KB Output is correct
35 Correct 31 ms 4600 KB Output is correct
36 Correct 24 ms 3856 KB Output is correct
37 Correct 11 ms 2900 KB Output is correct
38 Correct 30 ms 4488 KB Output is correct
39 Correct 31 ms 4644 KB Output is correct
40 Correct 9 ms 2900 KB Output is correct
41 Correct 23 ms 3284 KB Output is correct
42 Correct 27 ms 3796 KB Output is correct
43 Correct 33 ms 4572 KB Output is correct
44 Correct 33 ms 4556 KB Output is correct
45 Correct 27 ms 4268 KB Output is correct
46 Correct 37 ms 5204 KB Output is correct
47 Correct 56 ms 8316 KB Output is correct
48 Correct 6 ms 2760 KB Output is correct
49 Correct 63 ms 11408 KB Output is correct
50 Correct 49 ms 11348 KB Output is correct
51 Correct 0 ms 212 KB Output is correct
52 Correct 0 ms 212 KB Output is correct
53 Correct 0 ms 212 KB Output is correct
54 Correct 0 ms 212 KB Output is correct
55 Correct 1 ms 212 KB Output is correct
56 Correct 0 ms 212 KB Output is correct
57 Correct 0 ms 212 KB Output is correct
58 Correct 0 ms 212 KB Output is correct
59 Correct 0 ms 212 KB Output is correct
60 Correct 0 ms 212 KB Output is correct
61 Correct 0 ms 212 KB Output is correct
62 Correct 0 ms 212 KB Output is correct
63 Correct 0 ms 212 KB Output is correct
64 Correct 0 ms 212 KB Output is correct
65 Correct 1 ms 212 KB Output is correct
66 Correct 0 ms 212 KB Output is correct
67 Correct 0 ms 212 KB Output is correct
68 Correct 0 ms 212 KB Output is correct
69 Correct 1 ms 212 KB Output is correct
70 Correct 1 ms 212 KB Output is correct
71 Correct 1 ms 212 KB Output is correct
72 Correct 0 ms 212 KB Output is correct
73 Correct 1 ms 212 KB Output is correct
74 Correct 0 ms 212 KB Output is correct
75 Correct 0 ms 212 KB Output is correct
76 Correct 2 ms 468 KB Output is correct
77 Correct 1 ms 468 KB Output is correct
78 Correct 9 ms 1620 KB Output is correct
79 Correct 24 ms 5748 KB Output is correct
80 Correct 20 ms 3156 KB Output is correct
81 Correct 10 ms 2772 KB Output is correct
82 Correct 30 ms 4556 KB Output is correct
83 Correct 16 ms 3448 KB Output is correct
84 Correct 29 ms 4692 KB Output is correct
85 Correct 32 ms 4708 KB Output is correct
86 Correct 32 ms 5324 KB Output is correct
87 Correct 33 ms 5036 KB Output is correct
88 Correct 33 ms 4396 KB Output is correct
89 Correct 28 ms 4448 KB Output is correct
90 Correct 10 ms 2900 KB Output is correct
91 Correct 40 ms 4804 KB Output is correct
92 Correct 34 ms 4908 KB Output is correct
93 Correct 35 ms 4832 KB Output is correct
94 Correct 25 ms 4084 KB Output is correct
95 Correct 24 ms 4028 KB Output is correct
96 Correct 32 ms 5204 KB Output is correct
97 Correct 58 ms 8376 KB Output is correct
98 Correct 6 ms 2888 KB Output is correct
99 Correct 59 ms 11456 KB Output is correct
100 Correct 95 ms 11480 KB Output is correct