oj.uz

Submission #559839

# Submission time Handle Problem Language Result Execution time Memory
559839 2022-05-10T17:44:36 Z fatemetmhr Mousetrap (CEOI17_mousetrap) C++17
100 / 100
 672 ms 170596 KB 
// Be name khoda //
 
#include <bits/stdc++.h>
 
using namespace std;
 
typedef long long ll;
 
#define all(x)   x.begin(), x.end()
#define fi       first
#define se       second
#define pb       push_back
 
const int maxn5 = 1e6 + 10;
const int maxnt = 5e6 + 10;
const int inf   = 1e9;
 
int tale, mo, dp[maxn5], id[maxn5], newid = 0;
int htotale[maxn5], st[maxn5], parr[maxn5];
int valu[maxn5], valval[maxn5], zz[maxn5];
int cmp[maxn5];
vector <int> adj[maxn5], ver;
vector <pair<int, int>> av;
pair <int, int> mx[maxnt];
int mn[maxnt], lazy[maxnt], lazy2[maxnt];
 
inline bool dfs(int v, int par){
    if(v == tale){
        dp[v] = 0;
        htotale[v] = 0;
        return true;
    }
    int mx = 0, smx = 0;
    int z = -1;
    for(auto u : adj[v]) if(u != par){
        bool re = dfs(u, v);
        if(re){
            z = u;
        }
        if(dp[u] >= mx){
            smx = mx;
            mx = dp[u];
        }
        else
            smx = max(smx, dp[u]);
    }
    if(z == -1){
        dp[v] = smx + int(adj[v].size()) - 1;
        //cout << "false " << v << ' ' << dp[v] << endl;
        return false;
    }
 
    htotale[v] = htotale[z] + int(adj[v].size()) - 2 + (v == mo);
    ver.pb(v);
    parr[v] = par;
    zz[v] = z;
 
    //ft[ver.size()] = newid;
 
    return true;
}
 
 
inline bool ok(int v){
    for(int i = v; i <= ver.size(); i++){
        valval[i]--;
        if(valval[i] < 0)
            return false;
    }
    return true;
}
 
int main(){
    ios_base::sync_with_stdio(false); cin.tie(0); cout.tie(0);
 
    int n, a, b; cin >> n >> a >> b;
    a--; b--;
    mo = b;
    tale = a;
    for(int i = 0; i < n - 1; i++){
        int a, b; cin >> a >> b;
        a--; b--;
        adj[a].pb(b);
        adj[b].pb(a);
    }
 
    //assert(a != b);
 
    if(a == b)
        return cout << 0 << endl, 0;
 
    dfs(mo, -1);
 
    reverse(all(ver)); // az m be t hast
    //assert(ver.size() == 1);
 
    int mxx = 0, smx = 0;
    int pos = 1;
    for(auto v : ver){
        for(auto u : adj[v]) if(u != parr[v] && u != zz[v]){
            cmp[newid] = pos;
            valu[newid++] = dp[u] + htotale[v];
            //cout << v << ' ' << u << ' ' << dp[u] << ' ' << htotale[v] << endl;
            if(mxx <= dp[u] + htotale[v]){
                smx = mxx;
                mxx = dp[u] + htotale[v];
            }
            else
                smx = max(smx, dp[u] + htotale[v]);
            //cout << "aha " << v << ' ' << u << ' ' << dp[u] << ' ' << htotale[v] << endl;
        }
        st[pos] = newid;
        pos++;
    }
 
    //return cout << min(inf, smx) << endl, 0;
 
    
    //build(0, newid, 1);
    for(int i = 1; i <= ver.size(); i++)
        valval[i] = i;
    //build2(0, ver.size() + 1, 1);
 
    int done = 0;
    int ans = inf;
    //assert(st[pos - 1] == newid);
    //cout << newid << endl;
    if(newid == 0){
        return cout << 0 << endl, 0;
    }
    while(done < newid){
        int z = -1;
        for(int i = 0; i < newid; i++) if(z == -1 || valu[i] >= valu[z])
            z = i;
        //assert(done <= 1);
        ans = min(ans, valu[z] + done);
        //if(done == 1)
            //assert(mx[1].fi + done == smx);
        //if(done == 0)
            //assert(mx[1].fi == mxx);
        if(ok(cmp[z])){
            done++;
            for(int i = 0; i < st[cmp[z]]; i++)
                valu[i]--;
            valu[z] = -inf;
        }
        else
            break;
    }
    if(done == newid)
        ans = min(ans, done);
    //assert(done == 1);
    cout << ans << endl;
}

Compilation message

mousetrap.cpp: In function 'bool ok(int)':
mousetrap.cpp:65:22: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   65 |     for(int i = v; i <= ver.size(); i++){
      |                    ~~^~~~~~~~~~~~~
mousetrap.cpp: In function 'int main()':
mousetrap.cpp:120:22: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
  120 |     for(int i = 1; i <= ver.size(); i++)
      |                    ~~^~~~~~~~~~~~~

Subtask #1
20.0 / 20.0

# Verdict Execution time Memory Grader output
1 Correct 12 ms 23764 KB Output is correct
2 Correct 12 ms 23940 KB Output is correct
3 Correct 12 ms 23820 KB Output is correct
4 Correct 11 ms 23884 KB Output is correct
5 Correct 12 ms 23844 KB Output is correct
6 Correct 12 ms 23820 KB Output is correct
7 Correct 12 ms 23764 KB Output is correct
8 Correct 13 ms 23764 KB Output is correct
9 Correct 12 ms 23816 KB Output is correct
10 Correct 11 ms 23764 KB Output is correct

Subtask #2
25.0 / 25.0

# Verdict Execution time Memory Grader output
1 Correct 276 ms 58964 KB Output is correct
2 Correct 290 ms 64520 KB Output is correct
3 Correct 654 ms 68760 KB Output is correct
4 Correct 322 ms 48556 KB Output is correct
5 Correct 652 ms 68740 KB Output is correct
6 Correct 656 ms 68756 KB Output is correct

Subtask #3
20.0 / 20.0

# Verdict Execution time Memory Grader output
1 Correct 12 ms 23764 KB Output is correct
2 Correct 12 ms 23940 KB Output is correct
3 Correct 12 ms 23820 KB Output is correct
4 Correct 11 ms 23884 KB Output is correct
5 Correct 12 ms 23844 KB Output is correct
6 Correct 12 ms 23820 KB Output is correct
7 Correct 12 ms 23764 KB Output is correct
8 Correct 13 ms 23764 KB Output is correct
9 Correct 12 ms 23816 KB Output is correct
10 Correct 11 ms 23764 KB Output is correct
11 Correct 12 ms 23764 KB Output is correct
12 Correct 13 ms 23920 KB Output is correct
13 Correct 12 ms 23824 KB Output is correct
14 Correct 12 ms 24020 KB Output is correct
15 Correct 12 ms 23952 KB Output is correct
16 Correct 12 ms 23892 KB Output is correct
17 Correct 12 ms 23892 KB Output is correct
18 Correct 12 ms 23820 KB Output is correct
19 Correct 12 ms 23892 KB Output is correct
20 Correct 13 ms 23904 KB Output is correct
21 Correct 13 ms 23892 KB Output is correct
22 Correct 12 ms 23892 KB Output is correct

Subtask #4
35.0 / 35.0

# Verdict Execution time Memory Grader output
1 Correct 12 ms 23764 KB Output is correct
2 Correct 12 ms 23940 KB Output is correct
3 Correct 12 ms 23820 KB Output is correct
4 Correct 11 ms 23884 KB Output is correct
5 Correct 12 ms 23844 KB Output is correct
6 Correct 12 ms 23820 KB Output is correct
7 Correct 12 ms 23764 KB Output is correct
8 Correct 13 ms 23764 KB Output is correct
9 Correct 12 ms 23816 KB Output is correct
10 Correct 11 ms 23764 KB Output is correct
11 Correct 276 ms 58964 KB Output is correct
12 Correct 290 ms 64520 KB Output is correct
13 Correct 654 ms 68760 KB Output is correct
14 Correct 322 ms 48556 KB Output is correct
15 Correct 652 ms 68740 KB Output is correct
16 Correct 656 ms 68756 KB Output is correct
17 Correct 12 ms 23764 KB Output is correct
18 Correct 13 ms 23920 KB Output is correct
19 Correct 12 ms 23824 KB Output is correct
20 Correct 12 ms 24020 KB Output is correct
21 Correct 12 ms 23952 KB Output is correct
22 Correct 12 ms 23892 KB Output is correct
23 Correct 12 ms 23892 KB Output is correct
24 Correct 12 ms 23820 KB Output is correct
25 Correct 12 ms 23892 KB Output is correct
26 Correct 13 ms 23904 KB Output is correct
27 Correct 13 ms 23892 KB Output is correct
28 Correct 12 ms 23892 KB Output is correct
29 Correct 13 ms 23828 KB Output is correct
30 Correct 278 ms 72356 KB Output is correct
31 Correct 286 ms 72516 KB Output is correct
32 Correct 318 ms 170596 KB Output is correct
33 Correct 318 ms 150952 KB Output is correct
34 Correct 648 ms 73464 KB Output is correct
35 Correct 651 ms 73480 KB Output is correct
36 Correct 643 ms 85008 KB Output is correct
37 Correct 672 ms 85052 KB Output is correct
38 Correct 522 ms 86864 KB Output is correct
39 Correct 583 ms 86920 KB Output is correct
40 Correct 508 ms 86928 KB Output is correct