oj.uz

Submission #130839

# Submission time Handle Problem Language Result Execution time Memory
130839 2019-07-16T06:55:43 Z PeppaPig Valley (BOI19_valley) C++14
100 / 100
 266 ms 41436 KB 
#include <bits/stdc++.h>

#define long long long
#define pii pair<long, long>
#define x first
#define y second

using namespace std;

const int N = 1e5+5;

int n, s, q, e;
int u[N], v[N], w[N], in[N], out[N], pos[N];
int par[N][18], dep[N];
long d[N], dp[N], pre[N][18];
bitset<N> shop;
vector<pii> g[N];

void gen_lca(int u, int p) {
    static int idx = 0;
    in[u] = ++idx, pos[idx] = u;
    dep[u] = dep[p] + 1, par[u][0] = p;
    if(shop[u]) dp[u] = d[u];
    for(pii v : g[u]) if(v.x != p) {
        d[v.x] = d[u] + v.y;
        gen_lca(v.x, u);
        dp[u] = min(dp[u], dp[v.x]);
    }
    out[u] = idx;
}

int main() {
    fill_n(dp, N, 1e18), fill_n(pre[0], N * 18, 1e18);
    scanf("%d %d %d %d", &n, &s, &q, &e);
    for(int i = 1; i < n; i++) {
        scanf("%d %d %d", u + i, v + i, w + i);
        g[u[i]].emplace_back(v[i], w[i]);
        g[v[i]].emplace_back(u[i], w[i]); 
    }
    for(int i = 1, a; i <= s; i++) scanf("%d", &a), shop[a] = true;
    gen_lca(e, 0);
    for(int i = 1; i <= n; i++) if(dp[i] != 1e18) pre[i][0] = dp[i] - 2 * d[i];
    for(int t = 1; t <= n; t++) {
        int u = pos[t];
        for(int i = 1; i <= 17; i++) {
            par[u][i] = par[par[u][i-1]][i-1];
            pre[u][i] = min(pre[u][i-1], pre[par[u][i-1]][i-1]);
        }
    }
    for(int i = 1, a, b; i <= q; i++) {
        scanf("%d %d", &a, &b);
        int now = dep[u[a]] > dep[v[a]] ? u[a] : v[a];
        if(in[now] > in[b] || out[b] > out[now]) {
            printf("escaped\n");
            continue;
        }
        int dist = dep[b] - dep[now], u = b;
        long ans = 1e18;
        for(int i = 17; ~i; i--) if(dist >> i & 1) {
            ans = min(ans, pre[u][i]);
            u = par[u][i];
        }
        ans = min(ans, pre[u][0]);
        if(ans >= 1e18) printf("oo\n");
        else printf("%lld\n", ans + d[b]);
    }

    return 0;
}

Compilation message

valley.cpp: In function 'int main()':
valley.cpp:34:10: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
     scanf("%d %d %d %d", &n, &s, &q, &e);
     ~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
valley.cpp:36:14: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
         scanf("%d %d %d", u + i, v + i, w + i);
         ~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
valley.cpp:40:51: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
     for(int i = 1, a; i <= s; i++) scanf("%d", &a), shop[a] = true;
                                    ~~~~~~~~~~~~~~~^~~~~~~~~~~~~~~~
valley.cpp:51:14: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
         scanf("%d %d", &a, &b);
         ~~~~~^~~~~~~~~~~~~~~~~

Subtask #1
9.0 / 9.0

# Verdict Execution time Memory Grader output
1 Correct 20 ms 17656 KB Output is correct
2 Correct 20 ms 17784 KB Output is correct
3 Correct 20 ms 17784 KB Output is correct
4 Correct 20 ms 17784 KB Output is correct

Subtask #2
27.0 / 27.0

# Verdict Execution time Memory Grader output
1 Correct 20 ms 17656 KB Output is correct
2 Correct 20 ms 17784 KB Output is correct
3 Correct 20 ms 17784 KB Output is correct
4 Correct 20 ms 17784 KB Output is correct
5 Correct 18 ms 17784 KB Output is correct
6 Correct 18 ms 17784 KB Output is correct
7 Correct 18 ms 17788 KB Output is correct
8 Correct 18 ms 17712 KB Output is correct
9 Correct 18 ms 17784 KB Output is correct
10 Correct 18 ms 17784 KB Output is correct
11 Correct 21 ms 17784 KB Output is correct
12 Correct 18 ms 17784 KB Output is correct
13 Correct 18 ms 17784 KB Output is correct
14 Correct 18 ms 17784 KB Output is correct

Subtask #3
23.0 / 23.0

# Verdict Execution time Memory Grader output
1 Correct 209 ms 34024 KB Output is correct
2 Correct 221 ms 37684 KB Output is correct
3 Correct 228 ms 37832 KB Output is correct
4 Correct 244 ms 39288 KB Output is correct
5 Correct 228 ms 39496 KB Output is correct
6 Correct 265 ms 41156 KB Output is correct

Subtask #4
41.0 / 41.0

# Verdict Execution time Memory Grader output
1 Correct 20 ms 17656 KB Output is correct
2 Correct 20 ms 17784 KB Output is correct
3 Correct 20 ms 17784 KB Output is correct
4 Correct 20 ms 17784 KB Output is correct
5 Correct 18 ms 17784 KB Output is correct
6 Correct 18 ms 17784 KB Output is correct
7 Correct 18 ms 17788 KB Output is correct
8 Correct 18 ms 17712 KB Output is correct
9 Correct 18 ms 17784 KB Output is correct
10 Correct 18 ms 17784 KB Output is correct
11 Correct 21 ms 17784 KB Output is correct
12 Correct 18 ms 17784 KB Output is correct
13 Correct 18 ms 17784 KB Output is correct
14 Correct 18 ms 17784 KB Output is correct
15 Correct 209 ms 34024 KB Output is correct
16 Correct 221 ms 37684 KB Output is correct
17 Correct 228 ms 37832 KB Output is correct
18 Correct 244 ms 39288 KB Output is correct
19 Correct 228 ms 39496 KB Output is correct
20 Correct 265 ms 41156 KB Output is correct
21 Correct 191 ms 37220 KB Output is correct
22 Correct 200 ms 37164 KB Output is correct
23 Correct 203 ms 37372 KB Output is correct
24 Correct 222 ms 39032 KB Output is correct
25 Correct 266 ms 41436 KB Output is correct
26 Correct 219 ms 37236 KB Output is correct
27 Correct 202 ms 37040 KB Output is correct
28 Correct 220 ms 37328 KB Output is correct
29 Correct 234 ms 38520 KB Output is correct
30 Correct 252 ms 39928 KB Output is correct
31 Correct 192 ms 36088 KB Output is correct
32 Correct 199 ms 34040 KB Output is correct
33 Correct 225 ms 34204 KB Output is correct
34 Correct 244 ms 36384 KB Output is correct
35 Correct 234 ms 38648 KB Output is correct
36 Correct 215 ms 38776 KB Output is correct