oj.uz

Submission #230729

# Submission time Handle Problem Language Result Execution time Memory
230729 2020-05-11T13:36:21 Z emil_physmath File Paths (BOI15_fil) C++17
100 / 100
 429 ms 976 KB 
#include <unordered_map>
#include <algorithm>
#include <iostream>
#include <cstdio>
#include <limits>
#include <vector>
#include <map>
using namespace std;
 
vector<int> chld[6001];
int tin[6001], tout[6001], p[6001], len[6001], depth[6001];
 
inline bool Upper(int u, int v) { return tin[u] <= tin[v] && tout[u] >= tout[v]; }
void DFS(int v)
{
    static int time = 0;
    tin[v] = ++time;
    for (int to: chld[v])
        DFS(to);
    tout[v] = time;
}
int main()
{
    int n, m, des;
    cin >> n >> m >> des;
    int sym;
    cin >> sym;
    ++sym;
    p[0] = -1;
    for (int i = 1; i <= n + m; ++i)
    {
        scanf("%d%d", &p[i], &len[i]);
        chld[p[i]].push_back(i);
        ++len[i];
        depth[i] = depth[p[i]] + len[i];
    }
    DFS(0);
    vector<int> pref; pref.reserve(n + m);
    vector<int> prefv; prefv.reserve(n + m);
    vector<int> stNodes;
    for (int i = 0; i <= n; ++i)
        stNodes.push_back(i);
    sort(stNodes.begin(), stNodes.end(), [](int u, int v) {
         return depth[u] < depth[v];
    });
    for (int i = n + 1; i <= n + m; ++i)
    {
        pref.clear(); prefv.clear();
        for (int j = i; j != -1; j = p[j])
        {
            prefv.push_back(j);
            pref.push_back(depth[j]);
        }
        reverse(pref.begin(), pref.end());
        reverse(prefv.begin(), prefv.end());
        bool ans = pref.back() == des;
        for (int from = 0; !ans && from <= n; ++from)
            if (binary_search(pref.begin(), prev(pref.end()), depth[from] + sym + pref.back() - des))
            {
                ans = true;
                break;
            }
        if (des - pref.back() > 0)
        {
            for (int x = 1; !ans && x * x <= des - pref.back(); ++x)
                for (int y = 0; !ans && y <= 1; ++y, x = (des - pref.back()) / x)
                {
                    if ((des - pref.back()) % x) continue;
                    int i = 0;
                    for (int from: stNodes)
                    {
                        // depth[from] - depth[to] + sym == x
                        // depth[to] = depth[from] + sym - x
                        while (i + 1 < pref.size() && pref[i + 1] <= depth[from] + sym - x)
                            ++i;
                        if (pref[i] != depth[from] + sym - x) continue;
                        if (Upper(prefv[i], from))
                        {
                            ans = true;
                            break;
                        }
                    }
                }
        }
        printf(ans ? "YES\n" : "NO\n");
    }
}

Compilation message

fil.cpp: In function 'int main()':
fil.cpp:74:38: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
                         while (i + 1 < pref.size() && pref[i + 1] <= depth[from] + sym - x)
                                ~~~~~~^~~~~~~~~~~~~
fil.cpp:32:14: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
         scanf("%d%d", &p[i], &len[i]);
         ~~~~~^~~~~~~~~~~~~~~~~~~~~~~~

Subtask #1
33.0 / 33.0

# Verdict Execution time Memory Grader output
1 Correct 5 ms 512 KB Output is correct
2 Correct 7 ms 512 KB Output is correct
3 Correct 12 ms 512 KB Output is correct
4 Correct 14 ms 512 KB Output is correct
5 Correct 15 ms 512 KB Output is correct
6 Correct 13 ms 512 KB Output is correct
7 Correct 17 ms 512 KB Output is correct
8 Correct 11 ms 512 KB Output is correct
9 Correct 12 ms 512 KB Output is correct
10 Correct 5 ms 512 KB Output is correct
11 Correct 9 ms 512 KB Output is correct
12 Correct 12 ms 512 KB Output is correct

Subtask #2
33.0 / 33.0

# Verdict Execution time Memory Grader output
1 Correct 226 ms 640 KB Output is correct
2 Correct 238 ms 768 KB Output is correct
3 Correct 222 ms 768 KB Output is correct
4 Correct 222 ms 768 KB Output is correct
5 Correct 237 ms 896 KB Output is correct
6 Correct 169 ms 896 KB Output is correct
7 Correct 223 ms 864 KB Output is correct
8 Correct 184 ms 768 KB Output is correct
9 Correct 258 ms 888 KB Output is correct
10 Correct 245 ms 768 KB Output is correct
11 Correct 12 ms 768 KB Output is correct
12 Correct 194 ms 896 KB Output is correct

Subtask #3
34.0 / 34.0

# Verdict Execution time Memory Grader output
1 Correct 5 ms 512 KB Output is correct
2 Correct 7 ms 512 KB Output is correct
3 Correct 12 ms 512 KB Output is correct
4 Correct 14 ms 512 KB Output is correct
5 Correct 15 ms 512 KB Output is correct
6 Correct 13 ms 512 KB Output is correct
7 Correct 17 ms 512 KB Output is correct
8 Correct 11 ms 512 KB Output is correct
9 Correct 12 ms 512 KB Output is correct
10 Correct 5 ms 512 KB Output is correct
11 Correct 9 ms 512 KB Output is correct
12 Correct 12 ms 512 KB Output is correct
13 Correct 226 ms 640 KB Output is correct
14 Correct 238 ms 768 KB Output is correct
15 Correct 222 ms 768 KB Output is correct
16 Correct 222 ms 768 KB Output is correct
17 Correct 237 ms 896 KB Output is correct
18 Correct 169 ms 896 KB Output is correct
19 Correct 223 ms 864 KB Output is correct
20 Correct 184 ms 768 KB Output is correct
21 Correct 258 ms 888 KB Output is correct
22 Correct 245 ms 768 KB Output is correct
23 Correct 12 ms 768 KB Output is correct
24 Correct 194 ms 896 KB Output is correct
25 Correct 176 ms 768 KB Output is correct
26 Correct 171 ms 768 KB Output is correct
27 Correct 168 ms 768 KB Output is correct
28 Correct 194 ms 948 KB Output is correct
29 Correct 196 ms 896 KB Output is correct
30 Correct 200 ms 896 KB Output is correct
31 Correct 244 ms 888 KB Output is correct
32 Correct 236 ms 976 KB Output is correct
33 Correct 163 ms 768 KB Output is correct
34 Correct 157 ms 768 KB Output is correct
35 Correct 19 ms 768 KB Output is correct
36 Correct 429 ms 888 KB Output is correct