oj.uz

Submission #645406

# Submission time Handle Problem Language Result Execution time Memory
645406 2022-09-27T05:51:09 Z mychecksedad Love Polygon (BOI18_polygon) C++17
21 / 100
 2000 ms 44360 KB 
/* Author : Mychecksdead */
#include<bits/stdc++.h>
using namespace std;
typedef long long int ll;
typedef long double ld;
#define MOD (1000000000+7)
#define MOD1 (998244353)
#define PI 3.1415926535
#define pb push_back
#define setp() cout << setprecision(15)
#define all(x) x.begin(), x.end()
#define debug(x) cerr << #x << " is " << x << '\n';
const int N = 1e6+100, M = 1e5+10, F = 2147483646, K = 20;

int n, to[N], res = 0, dp[N][2];
string x, y;
vector<int> in(N), g[N];
map<string, int> s;
vector<bool> vis(N), is(N);

void dfs(int v, int d){
    vis[v] = 1;
    int u = to[v];
    if(vis[u]){
        if(d > 2) res += (d+1)/2;
        else if(d == 1) res++;
    }else dfs(u, d + 1);
}
void dfs1(int v){
    dp[v][0] = dp[v][1] = MOD;
    if(g[v].size() == 0){
        dp[v][0] = dp[v][1] = 1;
    }
    dp[v][0] = 1;
    int sum = 0;
    for(int u: g[v]){   
        dfs1(u);
        dp[v][0] += min(dp[u][0], dp[u][1]);
        sum += dp[u][1];
    }
    for(int u: g[v]){
        dp[v][1] = min(dp[v][1], sum - dp[u][1] + dp[u][0] - 1);
    }
}

void solve(){
    cin >> n;
    int c = 1;
    for(int i = 0; i < n; ++i){
        cin >> x >> y;
        if(s[x] == 0) s[x] = c++;
        if(s[y] == 0) s[y] = c++;
        int a = s[x] - 1, b = s[y] - 1;
        to[a] = b;
        is[b] = 1; 
        g[b].pb(a);
    }
    if(n&1){
        cout << -1;
        return;
    }
    if(n <= 20){
        int ans = n;
        for(int mask = 0; mask < (1<<n); ++mask){

            bool ok = 1;
            vector<int> v;

            for(int j = 0; j < n; ++j){
                if(!((1<<j)&mask)){
                    v.pb(to[j]);
                    if(to[j] == j) ok = 0;
                    else if(!(to[to[j]] == j || ((1<<to[j])&mask))) ok = 0;
                }
            }
            sort(all(v));
            
            for(int j = 0; j < int(v.size()) - 1; ++j) if(v[j] == v[j + 1]) ok = 0;
            

            if(ok){
                if(ans > __builtin_popcount(mask)){
                    ans = __builtin_popcount(mask);
                }
            }
        }
        cout << ans;
        return;
    }
    bool ok = 1;
    for(int i = 0; i < n; ++i) ok &= is[i];
    if(ok)
        for(int i = 0; i < n; ++i) if(!vis[i]) dfs(i, 1);
    else{
        for(int i = 0; i < 1e9; ++i) cout << "f" << endl;
        for(int i = 0; i < n; ++i) if(to[i] == i) dfs1(i), res += min(dp[i][0], dp[i][1]);
    }
    cout << res;
}





int main(){
    cin.tie(0); ios::sync_with_stdio(0);
    int T = 1, aa;
    // cin >> T;aa=T;
    while(T--){
        // cout << "Case #" << aa-T << ": ";
        solve();
        cout << '\n';
    }
    return 0;
 
}

Compilation message

polygon.cpp: In function 'void solve()':
polygon.cpp:92:7: warning: suggest explicit braces to avoid ambiguous 'else' [-Wdangling-else]
   92 |     if(ok)
      |       ^
polygon.cpp: In function 'int main()':
polygon.cpp:107:16: warning: unused variable 'aa' [-Wunused-variable]
  107 |     int T = 1, aa;
      |                ^~

Subtask #1
21.0 / 21.0

# Verdict Execution time Memory Grader output
1 Correct 297 ms 27968 KB Output is correct
2 Correct 248 ms 27908 KB Output is correct
3 Correct 290 ms 27988 KB Output is correct
4 Correct 13 ms 27932 KB Output is correct
5 Correct 15 ms 27988 KB Output is correct
6 Correct 12 ms 27908 KB Output is correct
7 Correct 268 ms 27952 KB Output is correct
8 Correct 283 ms 27988 KB Output is correct
9 Correct 278 ms 27880 KB Output is correct
10 Correct 278 ms 27988 KB Output is correct
11 Correct 280 ms 27984 KB Output is correct
12 Correct 13 ms 27988 KB Output is correct
13 Correct 14 ms 27892 KB Output is correct
14 Correct 16 ms 27988 KB Output is correct
15 Correct 15 ms 27872 KB Output is correct

Subtask #2
0 / 25.0

# Verdict Execution time Memory Grader output
1 Correct 14 ms 27952 KB Output is correct
2 Correct 14 ms 27888 KB Output is correct
3 Correct 14 ms 27960 KB Output is correct
4 Execution timed out 2082 ms 44360 KB Time limit exceeded
5 Halted 0 ms 0 KB -

Subtask #3
0 / 29.0

# Verdict Execution time Memory Grader output
1 Incorrect 204 ms 38464 KB Output isn't correct
2 Halted 0 ms 0 KB -

Subtask #4
0 / 25.0

# Verdict Execution time Memory Grader output
1 Correct 297 ms 27968 KB Output is correct
2 Correct 248 ms 27908 KB Output is correct
3 Correct 290 ms 27988 KB Output is correct
4 Correct 13 ms 27932 KB Output is correct
5 Correct 15 ms 27988 KB Output is correct
6 Correct 12 ms 27908 KB Output is correct
7 Correct 268 ms 27952 KB Output is correct
8 Correct 283 ms 27988 KB Output is correct
9 Correct 278 ms 27880 KB Output is correct
10 Correct 278 ms 27988 KB Output is correct
11 Correct 280 ms 27984 KB Output is correct
12 Correct 13 ms 27988 KB Output is correct
13 Correct 14 ms 27892 KB Output is correct
14 Correct 16 ms 27988 KB Output is correct
15 Correct 15 ms 27872 KB Output is correct
16 Correct 14 ms 27952 KB Output is correct
17 Correct 14 ms 27888 KB Output is correct
18 Correct 14 ms 27960 KB Output is correct
19 Execution timed out 2082 ms 44360 KB Time limit exceeded
20 Halted 0 ms 0 KB -