oj.uz

Submission #645404

# Submission time Handle Problem Language Result Execution time Memory
645404 2022-09-27T05:49:46 Z mychecksedad Love Polygon (BOI18_polygon) C++17
21 / 100
 602 ms 1048576 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 < 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:105:16: warning: unused variable 'aa' [-Wunused-variable]
  105 |     int T = 1, aa;
      |                ^~

Subtask #1
21.0 / 21.0

# Verdict Execution time Memory Grader output
1 Correct 276 ms 27988 KB Output is correct
2 Correct 250 ms 27972 KB Output is correct
3 Correct 298 ms 27988 KB Output is correct
4 Correct 17 ms 27920 KB Output is correct
5 Correct 13 ms 27988 KB Output is correct
6 Correct 13 ms 27988 KB Output is correct
7 Correct 290 ms 27972 KB Output is correct
8 Correct 309 ms 27988 KB Output is correct
9 Correct 273 ms 28116 KB Output is correct
10 Correct 297 ms 27988 KB Output is correct
11 Correct 289 ms 27988 KB Output is correct
12 Correct 17 ms 28012 KB Output is correct
13 Correct 15 ms 27988 KB Output is correct
14 Correct 14 ms 27988 KB Output is correct
15 Correct 13 ms 27984 KB Output is correct

Subtask #2
0 / 25.0

# Verdict Execution time Memory Grader output
1 Correct 13 ms 27988 KB Output is correct
2 Correct 13 ms 27956 KB Output is correct
3 Correct 15 ms 28076 KB Output is correct
4 Runtime error 602 ms 1048576 KB Execution killed with signal 9
5 Halted 0 ms 0 KB -

Subtask #3
0 / 29.0

# Verdict Execution time Memory Grader output
1 Incorrect 226 ms 40412 KB Output isn't correct
2 Halted 0 ms 0 KB -

Subtask #4
0 / 25.0

# Verdict Execution time Memory Grader output
1 Correct 276 ms 27988 KB Output is correct
2 Correct 250 ms 27972 KB Output is correct
3 Correct 298 ms 27988 KB Output is correct
4 Correct 17 ms 27920 KB Output is correct
5 Correct 13 ms 27988 KB Output is correct
6 Correct 13 ms 27988 KB Output is correct
7 Correct 290 ms 27972 KB Output is correct
8 Correct 309 ms 27988 KB Output is correct
9 Correct 273 ms 28116 KB Output is correct
10 Correct 297 ms 27988 KB Output is correct
11 Correct 289 ms 27988 KB Output is correct
12 Correct 17 ms 28012 KB Output is correct
13 Correct 15 ms 27988 KB Output is correct
14 Correct 14 ms 27988 KB Output is correct
15 Correct 13 ms 27984 KB Output is correct
16 Correct 13 ms 27988 KB Output is correct
17 Correct 13 ms 27956 KB Output is correct
18 Correct 15 ms 28076 KB Output is correct
19 Runtime error 602 ms 1048576 KB Execution killed with signal 9
20 Halted 0 ms 0 KB -