oj.uz

Submission #726404

# Submission time Handle Problem Language Result Execution time Memory
726404 2023-04-18T21:10:00 Z YugiHacker Mag (COCI16_mag) C++17
120 / 120
 544 ms 197736 KB 
/*
	www.youtube.com/YugiHackerChannel
	oj.vnoi.info/user/YugiHackerKhongCopCode
*/
#include<bits/stdc++.h>
#define el cout<<"\n"
#define f0(i,n) for(int i=0;i<n;++i)
#define f1(i,n) for(int i=1;i<=n;++i)
#define maxn 1000006
using namespace std;
struct frac
{
    long long x, y;
    frac(){}
    frac(long long x, long long y): x(x), y(y){}
    friend bool operator < (frac a, frac b)
    {
        return a.x * b.y < a.y * b.x;
    }
    void output()
    {
        long long g = __gcd(x, y);
        cout << x/g << '/' << y/g;
    }
}ans(1e9, 1);
int n;
vector <int> a[maxn];
int c[maxn];
int down[2][maxn], up[maxn]; ///h : update from v to u, d : update from par to u
void dfs(int u, int p)
{
    for (int v:a[u]) if (v != p)
    {
        dfs(v, u);
        if (c[v] == 1)
        {
            if (down[0][u] < down[0][v] + 1)
                down[1][u] = down[0][u], down[0][u] = down[0][v] + 1;
            else if (down[1][u] < down[0][v] + 1)
                down[1][u] = down[0][v] + 1;
        }

    }
}
void dfs$(int u, int p)
{
    for (int v:a[u]) if (v != p)
    {
        if (c[u] == 1)
        {
            up[v] = up[u] + 1;
            if (c[v] == 1)
            {
                if (down[0][v] + 1 == down[0][u]) up[v] = max(up[v], down[1][u] + 1);
            }
            else
            {
                up[v] = max(up[v], down[0][u] + 1);
            }
        }
        dfs$(v, u);
    }
    vector <int> tmp;
    tmp.push_back(up[u]);
    tmp.push_back(down[0][u]);
    tmp.push_back(down[1][u]);
    sort(tmp.begin(), tmp.end(), greater<int>());
    //cout << u << ' ' << down[0][u] << ' ' << down[1][u] << ' ' << up[u], el;
    ans = min(ans, frac(c[u], tmp[0] + tmp[1] + 1));
}
main()
{
    ios_base::sync_with_stdio(0);cin.tie(0);cout.tie(0);
    cin >> n;
    f1 (i, n-1)
    {
        int u, v; cin >> u >> v;
        a[u].push_back(v);
        a[v].push_back(u);
    }
    f1 (i, n) cin >> c[i];
    dfs(1, 0);
    dfs$(1, 0);
    ans.output();
}

Compilation message

mag.cpp:71:1: warning: ISO C++ forbids declaration of 'main' with no type [-Wreturn-type]
   71 | main()
      | ^~~~

Subtask #1
12.0 / 12.0

# Verdict Execution time Memory Grader output
1 Correct 14 ms 23820 KB Output is correct
2 Correct 17 ms 23824 KB Output is correct

Subtask #2
12.0 / 12.0

# Verdict Execution time Memory Grader output
1 Correct 13 ms 23892 KB Output is correct
2 Correct 15 ms 23852 KB Output is correct

Subtask #3
12.0 / 12.0

# Verdict Execution time Memory Grader output
1 Correct 398 ms 119264 KB Output is correct

Subtask #4
12.0 / 12.0

# Verdict Execution time Memory Grader output
1 Correct 13 ms 23764 KB Output is correct
2 Correct 544 ms 194292 KB Output is correct

Subtask #5
12.0 / 12.0

# Verdict Execution time Memory Grader output
1 Correct 513 ms 193480 KB Output is correct

Subtask #6
12.0 / 12.0

# Verdict Execution time Memory Grader output
1 Correct 429 ms 85884 KB Output is correct
2 Correct 315 ms 69580 KB Output is correct

Subtask #7
12.0 / 12.0

# Verdict Execution time Memory Grader output
1 Correct 446 ms 88808 KB Output is correct
2 Correct 96 ms 30184 KB Output is correct
3 Correct 516 ms 197736 KB Output is correct

Subtask #8
12.0 / 12.0

# Verdict Execution time Memory Grader output
1 Correct 96 ms 29984 KB Output is correct
2 Correct 423 ms 86664 KB Output is correct
3 Correct 311 ms 55364 KB Output is correct

Subtask #9
12.0 / 12.0

# Verdict Execution time Memory Grader output
1 Correct 390 ms 83892 KB Output is correct
2 Correct 407 ms 86944 KB Output is correct

Subtask #10
12.0 / 12.0

# Verdict Execution time Memory Grader output
1 Correct 431 ms 86876 KB Output is correct
2 Correct 428 ms 55440 KB Output is correct