oj.uz

Submission #225743

# Submission time Handle Problem Language Result Execution time Memory
225743 2020-04-21T13:13:31 Z osaaateiasavtnl Mag (COCI16_mag) C++14
120 / 120
 653 ms 252664 KB 
#include<bits/stdc++.h>
using namespace std;
#define int long long
#define ii pair <int, int>
#define app push_back
#define all(a) a.begin(), a.end()
#define bp __builtin_popcount
#define ll long long
#define mp make_pair
#define f first
#define s second
#define Time (double)clock()/CLOCKS_PER_SEC

const int N = 1e6 + 7, INF = 1e9 + 7;
int n, a[N];
vector <int> g[N];
int x, y;
void relax(int a, int b) {
    if (a * y < x * b) {
        x = a;
        y = b;
    }   
}   
int down[N];
void dfs1(int u, int p) {
    down[u] = a[u] == 1;
    for (int v : g[u]) {
        if (v != p) {
            dfs1(v, u);
            if (a[u] == 1)
                down[u] = max(down[u], down[v] + 1);            
        }   
    }   
}   
int up[N];
void dfs2(int u, int p) {
    vector <int> d = {0, 0};
    for (int v : g[u]) {
        if (v != p) {
            d.app(down[v]);
        }   
    }
    sort(all(d));                                    
    reverse(all(d));
    for (int v : g[u]) {
        if (v != p) {
            if (a[u] != 1) {
                up[v] = 0;
            }
            else {
                int h = d[d[0] == down[v]];
                up[v] = max(up[u], h) + 1;
            }
            dfs2(v, u);
        }   
    }   
    relax(a[u], d[0] + d[1] + 1);
    relax(a[u], up[u] + d[0] + 1);
}   
signed main() {
    #ifdef HOME
    freopen("input.txt", "r", stdin);
    #else
    #define endl '\n'
    ios_base::sync_with_stdio(0); cin.tie(0);
    #endif
    cin >> n;
    for (int i = 0; i < n - 1; ++i) {
        int u, v;
        cin >> u >> v;
        g[u].app(v); g[v].app(u);
    }   
    x = INF;
    y = 1;
    for (int i = 1; i <= n; ++i) {
        cin >> a[i];
        relax(a[i], 1);
    }
    dfs1(1, 1);
    dfs2(1, 1);

    int t = __gcd(x, y);
    x /= t; y /= t;

    cout << x << '/' << y << endl;
}

Subtask #1
12.0 / 12.0

# Verdict Execution time Memory Grader output
1 Correct 21 ms 23936 KB Output is correct
2 Correct 18 ms 23808 KB Output is correct

Subtask #2
12.0 / 12.0

# Verdict Execution time Memory Grader output
1 Correct 20 ms 23936 KB Output is correct
2 Correct 18 ms 23936 KB Output is correct

Subtask #3
12.0 / 12.0

# Verdict Execution time Memory Grader output
1 Correct 494 ms 130296 KB Output is correct

Subtask #4
12.0 / 12.0

# Verdict Execution time Memory Grader output
1 Correct 18 ms 23808 KB Output is correct
2 Correct 653 ms 248592 KB Output is correct

Subtask #5
12.0 / 12.0

# Verdict Execution time Memory Grader output
1 Correct 649 ms 229980 KB Output is correct

Subtask #6
12.0 / 12.0

# Verdict Execution time Memory Grader output
1 Correct 516 ms 78456 KB Output is correct
2 Correct 381 ms 75640 KB Output is correct

Subtask #7
12.0 / 12.0

# Verdict Execution time Memory Grader output
1 Correct 518 ms 83448 KB Output is correct
2 Correct 92 ms 31480 KB Output is correct
3 Correct 651 ms 252664 KB Output is correct

Subtask #8
12.0 / 12.0

# Verdict Execution time Memory Grader output
1 Correct 94 ms 29944 KB Output is correct
2 Correct 535 ms 95096 KB Output is correct
3 Correct 406 ms 61944 KB Output is correct

Subtask #9
12.0 / 12.0

# Verdict Execution time Memory Grader output
1 Correct 481 ms 77452 KB Output is correct
2 Correct 529 ms 94968 KB Output is correct

Subtask #10
12.0 / 12.0

# Verdict Execution time Memory Grader output
1 Correct 523 ms 79736 KB Output is correct
2 Correct 430 ms 62072 KB Output is correct