답안 #1000809

#	제출 시각	아이디	문제	언어	결과	실행 시간	메모리
1000809	2024-06-18T09:31:17 Z	saayan007	경주 (Race) (IOI11_race)	C++17	100 / 100	299 ms	32536 KB

race

/*

This problem can be found at https://oj.uz/problem/view/IOI11_race.

SOLUTION

Consider the problem of finding a path of length K containing minimum edges THAT GOES A FIXED NODE x.
This can be done in O(Size of Tree) time. Once this is done, we can remove the node x and edges connected to it. Then we can solve the problem for the remaining connected components.

The best choice of x is the centroid of the tree.

*/ 

#include "race.h"
#include "bits/stdc++.h"
using namespace std;
 
const int mxN = 2e5L + 10;
const int mxK = 1e6L + 10;
int n, k;
vector<pair<int, int>> adj[mxN];
int ans = mxN;
int sz[mxN];
bool proc[mxN] = {};
int dp[mxK];
 
int get_sz(int x, int p) {
    sz[x] = 1;
    for(auto [y, w] : adj[x]) {
        if(proc[y] || y == p) continue;
        sz[x] += get_sz(y, x);
    }
    return sz[x];
}
 
int get_cen(int x, int p, int tot) {
    for(auto [y, w] : adj[x]) {
        if(proc[y] || y == p || sz[y] * 2 <= tot) continue;
        return get_cen(y, x, tot);
    }
    return x;
}
 
void dfs(int x, int p, int dep, int dis, int flag) {
    if(dis > k) return;
    if(flag == 0) {
        if(dp[k - dis] != mxN) ans = min(ans, dep + dp[k - dis]);
    }
    else if(flag == 1) {
        dp[dis] = min(dp[dis], dep);
    }
    else if(flag == 2) {
        dp[dis] = mxN;
    }
 
    for(auto [y, w] : adj[x]) {
        if(proc[y] || y == p) continue;
        dfs(y, x, dep + 1, dis + w, flag);
    }
}
 
void solve(int x = 1, int p = -1) {
    int c = get_cen(x, p, get_sz(x, p));
    dp[0] = 0;
    for(auto [d, w] : adj[c]) {
        if(proc[d]) continue;
        dfs(d, c, 1, w, 0);
        dfs(d, c, 1, w, 1);
    }
    for(auto [d, w] : adj[c]) {
        if(proc[d]) continue;
        dfs(d, c, 1, w, 2);
    }
    dp[0] = mxN;
    proc[c] = 1;
    for(auto [d, w] : adj[c]) {
        if(proc[d]) continue;
        solve(d, c);
    }
}
 
int best_path(int N, int K, int H[][2], int L[])
{
    for(int i = 0; i < mxK; ++i) dp[i] = mxN;
    n = N; k = K;
    for(int i = 0; i < n - 1; ++i) {
        adj[H[i][0] + 1].emplace_back(H[i][1] + 1, L[i]);
        adj[H[i][1] + 1].emplace_back(H[i][0] + 1, L[i]);
    }
 
    solve();
    return (ans > n - 1 ? -1 : ans);
}

Subtask #1
9.0 / 9.0

#	결과	실행 시간	메모리	Grader output
1	Correct	4 ms	9052 KB	Output is correct
2	Correct	4 ms	9052 KB	Output is correct
3	Correct	4 ms	8920 KB	Output is correct
4	Correct	4 ms	9052 KB	Output is correct
5	Correct	4 ms	9052 KB	Output is correct
6	Correct	4 ms	9052 KB	Output is correct
7	Correct	4 ms	9052 KB	Output is correct
8	Correct	4 ms	9052 KB	Output is correct
9	Correct	3 ms	9052 KB	Output is correct
10	Correct	4 ms	9052 KB	Output is correct
11	Correct	4 ms	8844 KB	Output is correct
12	Correct	4 ms	9052 KB	Output is correct
13	Correct	4 ms	9052 KB	Output is correct
14	Correct	4 ms	9052 KB	Output is correct
15	Correct	3 ms	9052 KB	Output is correct
16	Correct	4 ms	9052 KB	Output is correct
17	Correct	4 ms	9052 KB	Output is correct
18	Correct	4 ms	9052 KB	Output is correct

Subtask #2
12.0 / 12.0

#	결과	실행 시간	메모리	Grader output
1	Correct	4 ms	9052 KB	Output is correct
2	Correct	4 ms	9052 KB	Output is correct
3	Correct	4 ms	8920 KB	Output is correct
4	Correct	4 ms	9052 KB	Output is correct
5	Correct	4 ms	9052 KB	Output is correct
6	Correct	4 ms	9052 KB	Output is correct
7	Correct	4 ms	9052 KB	Output is correct
8	Correct	4 ms	9052 KB	Output is correct
9	Correct	3 ms	9052 KB	Output is correct
10	Correct	4 ms	9052 KB	Output is correct
11	Correct	4 ms	8844 KB	Output is correct
12	Correct	4 ms	9052 KB	Output is correct
13	Correct	4 ms	9052 KB	Output is correct
14	Correct	4 ms	9052 KB	Output is correct
15	Correct	3 ms	9052 KB	Output is correct
16	Correct	4 ms	9052 KB	Output is correct
17	Correct	4 ms	9052 KB	Output is correct
18	Correct	4 ms	9052 KB	Output is correct
19	Correct	3 ms	9052 KB	Output is correct
20	Correct	3 ms	9052 KB	Output is correct
21	Correct	4 ms	9052 KB	Output is correct
22	Correct	4 ms	9052 KB	Output is correct
23	Correct	4 ms	9052 KB	Output is correct
24	Correct	4 ms	9052 KB	Output is correct
25	Correct	4 ms	9052 KB	Output is correct
26	Correct	4 ms	9012 KB	Output is correct
27	Correct	4 ms	9052 KB	Output is correct
28	Correct	4 ms	9052 KB	Output is correct
29	Correct	4 ms	8992 KB	Output is correct
30	Correct	4 ms	8980 KB	Output is correct
31	Correct	4 ms	9048 KB	Output is correct
32	Correct	4 ms	9052 KB	Output is correct
33	Correct	8 ms	9052 KB	Output is correct
34	Correct	5 ms	9052 KB	Output is correct
35	Correct	4 ms	9052 KB	Output is correct
36	Correct	4 ms	9052 KB	Output is correct
37	Correct	4 ms	9052 KB	Output is correct
38	Correct	4 ms	9052 KB	Output is correct

Subtask #3
22.0 / 22.0

#	결과	실행 시간	메모리	Grader output
1	Correct	4 ms	9052 KB	Output is correct
2	Correct	4 ms	9052 KB	Output is correct
3	Correct	4 ms	8920 KB	Output is correct
4	Correct	4 ms	9052 KB	Output is correct
5	Correct	4 ms	9052 KB	Output is correct
6	Correct	4 ms	9052 KB	Output is correct
7	Correct	4 ms	9052 KB	Output is correct
8	Correct	4 ms	9052 KB	Output is correct
9	Correct	3 ms	9052 KB	Output is correct
10	Correct	4 ms	9052 KB	Output is correct
11	Correct	4 ms	8844 KB	Output is correct
12	Correct	4 ms	9052 KB	Output is correct
13	Correct	4 ms	9052 KB	Output is correct
14	Correct	4 ms	9052 KB	Output is correct
15	Correct	3 ms	9052 KB	Output is correct
16	Correct	4 ms	9052 KB	Output is correct
17	Correct	4 ms	9052 KB	Output is correct
18	Correct	4 ms	9052 KB	Output is correct
19	Correct	89 ms	14420 KB	Output is correct
20	Correct	85 ms	15440 KB	Output is correct
21	Correct	102 ms	15304 KB	Output is correct
22	Correct	85 ms	15700 KB	Output is correct
23	Correct	47 ms	15960 KB	Output is correct
24	Correct	36 ms	15700 KB	Output is correct
25	Correct	92 ms	18348 KB	Output is correct
26	Correct	69 ms	20756 KB	Output is correct
27	Correct	101 ms	21328 KB	Output is correct
28	Correct	153 ms	32536 KB	Output is correct
29	Correct	149 ms	31828 KB	Output is correct
30	Correct	98 ms	21840 KB	Output is correct
31	Correct	116 ms	21844 KB	Output is correct
32	Correct	111 ms	21840 KB	Output is correct
33	Correct	138 ms	21060 KB	Output is correct
34	Correct	112 ms	20800 KB	Output is correct

Subtask #4
57.0 / 57.0

#	결과	실행 시간	메모리	Grader output
1	Correct	4 ms	9052 KB	Output is correct
2	Correct	4 ms	9052 KB	Output is correct
3	Correct	4 ms	8920 KB	Output is correct
4	Correct	4 ms	9052 KB	Output is correct
5	Correct	4 ms	9052 KB	Output is correct
6	Correct	4 ms	9052 KB	Output is correct
7	Correct	4 ms	9052 KB	Output is correct
8	Correct	4 ms	9052 KB	Output is correct
9	Correct	3 ms	9052 KB	Output is correct
10	Correct	4 ms	9052 KB	Output is correct
11	Correct	4 ms	8844 KB	Output is correct
12	Correct	4 ms	9052 KB	Output is correct
13	Correct	4 ms	9052 KB	Output is correct
14	Correct	4 ms	9052 KB	Output is correct
15	Correct	3 ms	9052 KB	Output is correct
16	Correct	4 ms	9052 KB	Output is correct
17	Correct	4 ms	9052 KB	Output is correct
18	Correct	4 ms	9052 KB	Output is correct
19	Correct	3 ms	9052 KB	Output is correct
20	Correct	3 ms	9052 KB	Output is correct
21	Correct	4 ms	9052 KB	Output is correct
22	Correct	4 ms	9052 KB	Output is correct
23	Correct	4 ms	9052 KB	Output is correct
24	Correct	4 ms	9052 KB	Output is correct
25	Correct	4 ms	9052 KB	Output is correct
26	Correct	4 ms	9012 KB	Output is correct
27	Correct	4 ms	9052 KB	Output is correct
28	Correct	4 ms	9052 KB	Output is correct
29	Correct	4 ms	8992 KB	Output is correct
30	Correct	4 ms	8980 KB	Output is correct
31	Correct	4 ms	9048 KB	Output is correct
32	Correct	4 ms	9052 KB	Output is correct
33	Correct	8 ms	9052 KB	Output is correct
34	Correct	5 ms	9052 KB	Output is correct
35	Correct	4 ms	9052 KB	Output is correct
36	Correct	4 ms	9052 KB	Output is correct
37	Correct	4 ms	9052 KB	Output is correct
38	Correct	4 ms	9052 KB	Output is correct
39	Correct	89 ms	14420 KB	Output is correct
40	Correct	85 ms	15440 KB	Output is correct
41	Correct	102 ms	15304 KB	Output is correct
42	Correct	85 ms	15700 KB	Output is correct
43	Correct	47 ms	15960 KB	Output is correct
44	Correct	36 ms	15700 KB	Output is correct
45	Correct	92 ms	18348 KB	Output is correct
46	Correct	69 ms	20756 KB	Output is correct
47	Correct	101 ms	21328 KB	Output is correct
48	Correct	153 ms	32536 KB	Output is correct
49	Correct	149 ms	31828 KB	Output is correct
50	Correct	98 ms	21840 KB	Output is correct
51	Correct	116 ms	21844 KB	Output is correct
52	Correct	111 ms	21840 KB	Output is correct
53	Correct	138 ms	21060 KB	Output is correct
54	Correct	112 ms	20800 KB	Output is correct
55	Correct	10 ms	9560 KB	Output is correct
56	Correct	10 ms	9596 KB	Output is correct
57	Correct	52 ms	14804 KB	Output is correct
58	Correct	28 ms	15568 KB	Output is correct
59	Correct	71 ms	20820 KB	Output is correct
60	Correct	299 ms	32128 KB	Output is correct
61	Correct	123 ms	21328 KB	Output is correct
62	Correct	117 ms	21768 KB	Output is correct
63	Correct	159 ms	21844 KB	Output is correct
64	Correct	280 ms	20560 KB	Output is correct
65	Correct	112 ms	22652 KB	Output is correct
66	Correct	246 ms	27988 KB	Output is correct
67	Correct	64 ms	23240 KB	Output is correct
68	Correct	151 ms	22276 KB	Output is correct
69	Correct	142 ms	20252 KB	Output is correct
70	Correct	135 ms	21836 KB	Output is correct

답안 #1000809

Compilation message

Subtask #1 9.0 / 9.0

Subtask #2 12.0 / 12.0

Subtask #3 22.0 / 22.0

Subtask #4 57.0 / 57.0

Subtask #1
9.0 / 9.0

Subtask #2
12.0 / 12.0

Subtask #3
22.0 / 22.0

Subtask #4
57.0 / 57.0