oj.uz

Submission #55566

# Submission time Handle Problem Language Result Execution time Memory
55566 2018-07-08T04:46:33 Z BThero Hard route (IZhO17_road) C++14
19 / 100
 2000 ms 12992 KB 
// Why I am so dumb? :c
#include <bits/stdc++.h>

#define pb push_back
#define mp make_pair

#define all(x) (x).begin(), (x).end()

#define fi first
#define se second

using namespace std;

typedef long long ll;

const int MAXN = 5e5+5;

vector<int> adj[MAXN];

pair<int, int> mxP1[MAXN];

vector<pair<int, int>> S; 

int dist[MAXN];

int par[MAXN];

int mxP2[MAXN];

int d[MAXN];

int ans1, ans2;

int n;

void dfs(int v, int pr) {
    mxP1[v] = mp(0, -1);
    mxP2[v] = d[v] = 0;

    for (int to : adj[v]) {
        if (to == pr) {
            continue;
        }

        dfs(to, v);

        if (mxP1[to].fi + 1 > mxP1[v].fi) {
            mxP2[v] = mxP1[v].fi;
            mxP1[v] = mp(mxP1[to].fi + 1, to);
        } 
        else if (mxP1[to].fi + 1 > mxP2[v]) {
            mxP2[v] = mxP1[to].fi + 1;
        }
    }
}

void dfs2(int v, int pr) {
    for (int to : adj[v]) {
        if (to == pr) {
            continue;
        }

        d[to] = max(d[to], d[v] + 1);

        if (mxP1[v].se == to) {
            d[to] = max(d[to], mxP2[v] + 1);
        }
        else {
            d[to] = max(d[to], mxP1[v].fi + 1);
        }

        dfs2(to, v);
    }
}

void goLeaf(int v, int pr) {
    if (adj[v].size() == 1) {
        S.pb(mp(v, 0));
    }

    for (int to : adj[v]) {
        if (to == pr) {
            continue;
        }

        goLeaf(to, v);
    }
}

void getPath(int v, int pr, int en) {
    if (v == en) {
        return;
    }

    for (int to : adj[v]) {
        if (to == pr) {
            continue;
        }

        par[to] = v;
        getPath(to, v, en);
    }
}

int getMx(vector<int> vv) {
    static queue<int> q;

    for (int i = 1; i <= n; ++i) {
        d[i] = n + 1;
    }

    for (int x : vv) {
        d[x] = 0;
        q.push(x);
    }

    while (!q.empty()) {
        int v = q.front();
        q.pop();

        for (int to : adj[v]) {
            if (d[to] == n + 1) {
                d[to] = d[v] + 1;
                q.push(to);
            }
        }
    }

    return *max_element(d + 1, d + n + 1);
}      

void solve() {
    scanf("%d", &n);

    for (int i = 1; i < n; ++i) {
        int u, v;
        scanf("%d %d", &u, &v);
        adj[u].pb(v);
        adj[v].pb(u);
    }

    dfs(1, -1);
    dfs2(1, -1);

    for (int i = 1; i <= n; ++i) {
        d[i] = max(d[i], mxP1[i].fi);
    }
                  
    goLeaf(1, -1);
    vector<int> vv;

    for (int i = 0; i < S.size(); ++i) {
        for (int j = i + 1; j < S.size(); ++j) {
            par[S[i].fi] = 0;            
            getPath(S[i].fi, -1, S[j].fi);
            vv.clear();

            for (int x = S[j].fi; x; x = par[x]) {
                vv.pb(x);
            }

            int dist = vv.size() - 1;
            int mx = getMx(vv);

            int cur = mx * dist;

            if (cur > ans1) {
                ans1 = cur;
                ans2 = 0;
            }

            if (cur == ans1) {
                ++ans2;
            }
        }
    }

    printf("%d %d\n", ans1, ans2);
}

int main() {            
    int tt = 1;

    while (tt--) {
        solve();
    }

    return 0;
}

Compilation message

road.cpp: In function 'void solve()':
road.cpp:152:23: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
     for (int i = 0; i < S.size(); ++i) {
                     ~~^~~~~~~~~~
road.cpp:153:31: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
         for (int j = i + 1; j < S.size(); ++j) {
                             ~~^~~~~~~~~~
road.cpp:133:10: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
     scanf("%d", &n);
     ~~~~~^~~~~~~~~~
road.cpp:137:14: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
         scanf("%d %d", &u, &v);
         ~~~~~^~~~~~~~~~~~~~~~~

Subtask #1
19.0 / 19.0

# Verdict Execution time Memory Grader output
1 Correct 11 ms 12152 KB Output is correct
2 Correct 11 ms 12152 KB Output is correct
3 Correct 11 ms 12212 KB Output is correct
4 Correct 11 ms 12212 KB Output is correct
5 Correct 11 ms 12312 KB Output is correct
6 Correct 11 ms 12372 KB Output is correct
7 Correct 14 ms 12372 KB Output is correct
8 Correct 13 ms 12372 KB Output is correct
9 Correct 14 ms 12432 KB Output is correct
10 Correct 13 ms 12432 KB Output is correct
11 Correct 14 ms 12432 KB Output is correct
12 Correct 14 ms 12432 KB Output is correct
13 Correct 14 ms 12432 KB Output is correct
14 Correct 14 ms 12432 KB Output is correct
15 Correct 12 ms 12432 KB Output is correct
16 Correct 14 ms 12552 KB Output is correct
17 Correct 14 ms 12552 KB Output is correct
18 Correct 14 ms 12564 KB Output is correct
19 Correct 15 ms 12564 KB Output is correct
20 Correct 14 ms 12564 KB Output is correct
21 Correct 14 ms 12564 KB Output is correct
22 Correct 13 ms 12564 KB Output is correct
23 Correct 15 ms 12600 KB Output is correct
24 Correct 21 ms 12604 KB Output is correct

Subtask #2
0 / 33.0

# Verdict Execution time Memory Grader output
1 Correct 11 ms 12152 KB Output is correct
2 Correct 11 ms 12152 KB Output is correct
3 Correct 11 ms 12212 KB Output is correct
4 Correct 11 ms 12212 KB Output is correct
5 Correct 11 ms 12312 KB Output is correct
6 Correct 11 ms 12372 KB Output is correct
7 Correct 14 ms 12372 KB Output is correct
8 Correct 13 ms 12372 KB Output is correct
9 Correct 14 ms 12432 KB Output is correct
10 Correct 13 ms 12432 KB Output is correct
11 Correct 14 ms 12432 KB Output is correct
12 Correct 14 ms 12432 KB Output is correct
13 Correct 14 ms 12432 KB Output is correct
14 Correct 14 ms 12432 KB Output is correct
15 Correct 12 ms 12432 KB Output is correct
16 Correct 14 ms 12552 KB Output is correct
17 Correct 14 ms 12552 KB Output is correct
18 Correct 14 ms 12564 KB Output is correct
19 Correct 15 ms 12564 KB Output is correct
20 Correct 14 ms 12564 KB Output is correct
21 Correct 14 ms 12564 KB Output is correct
22 Correct 13 ms 12564 KB Output is correct
23 Correct 15 ms 12600 KB Output is correct
24 Correct 21 ms 12604 KB Output is correct
25 Execution timed out 2053 ms 12992 KB Time limit exceeded
26 Halted 0 ms 0 KB -

Subtask #3
0 / 48.0

# Verdict Execution time Memory Grader output
1 Correct 11 ms 12152 KB Output is correct
2 Correct 11 ms 12152 KB Output is correct
3 Correct 11 ms 12212 KB Output is correct
4 Correct 11 ms 12212 KB Output is correct
5 Correct 11 ms 12312 KB Output is correct
6 Correct 11 ms 12372 KB Output is correct
7 Correct 14 ms 12372 KB Output is correct
8 Correct 13 ms 12372 KB Output is correct
9 Correct 14 ms 12432 KB Output is correct
10 Correct 13 ms 12432 KB Output is correct
11 Correct 14 ms 12432 KB Output is correct
12 Correct 14 ms 12432 KB Output is correct
13 Correct 14 ms 12432 KB Output is correct
14 Correct 14 ms 12432 KB Output is correct
15 Correct 12 ms 12432 KB Output is correct
16 Correct 14 ms 12552 KB Output is correct
17 Correct 14 ms 12552 KB Output is correct
18 Correct 14 ms 12564 KB Output is correct
19 Correct 15 ms 12564 KB Output is correct
20 Correct 14 ms 12564 KB Output is correct
21 Correct 14 ms 12564 KB Output is correct
22 Correct 13 ms 12564 KB Output is correct
23 Correct 15 ms 12600 KB Output is correct
24 Correct 21 ms 12604 KB Output is correct
25 Execution timed out 2053 ms 12992 KB Time limit exceeded
26 Halted 0 ms 0 KB -