oj.uz

Submission #1042408

# Submission time Handle Problem Language Result Execution time Memory
1042408 2024-08-03T03:58:58 Z sleepntsheep Inside information (BOI21_servers) C
50 / 100
 113 ms 30404 KB 
/* WHAT IS EXTRA INFORAMZTION GTR RR */

#include <stdio.h>
#include <stdlib.h>

/*
 * For "Q" queries, use LCA + prefix sum on tree ~ 3O(lgn) [for finding lca and almost-lca]
 *
 * Every B queries of any type, do naive dp on tree (reverse edge order)
 * to find answer for "C" queries  ~ O(n)
 *
 * On "C" queries, use cached answer from above and count all edges that appeared after that (by "Q")
 * ~ O(B lgn)
 *
 *
 * Time complexity = O(N^2 / B) + O(N lgn) + O(N B lgn)
 *
 * Let B = sqrt(N / lgN)
 */

#define N 120001
#define B 300

int max(int i, int j) {return i > j ? i : j;}

int n, q, pp[N], jj[N], dd[N], up[N], temp, inc[N];

void pus_(int **eh, int *eo, int i, int j) {
    int o = eo[i]++;
    if (0 == o) eh[i] = (int*)malloc(2 * sizeof **eh);
    else if (0 == (o & o - 1)) eh[i] = (int*)realloc(eh[i], 2 * o * sizeof **eh);
    eh[i][o] = j;
}

int *eh[N], *fh[N], eo[N];

void link(int u, int v, int w) {
    pus_(eh, eo, u, v);
    --eo[u];
    pus_(fh, eo, u, w);
    pus_(eh, eo, v, u);
    --eo[v];
    pus_(fh, eo, v, w);
}

void dfs(int u, int p) {
    inc[u] = (up[u] > up[p]) + inc[p];
    for (int j = 0; j < eo[u]; ++j) if (eh[u][j] != p) {
        int v = eh[u][j];
        dd[v] = dd[u] + 1;
        pp[v] = u;
        jj[v] = (dd[u] - dd[jj[u]] == dd[jj[u]] - dd[jj[jj[u]]]) ? jj[jj[u]]: u;
        up[v] = fh[u][j];
        dfs(v, u);
    }
}

int lca(int u, int v) {
    while (dd[u] != dd[v]) {
        if (dd[u] < dd[v]) temp = u, u = v, v = temp;
        u = (dd[jj[u]] >= dd[v]) ? jj[u] : pp[u];
    }
    while (u != v)
        if (jj[u] != jj[v]) u = jj[u], v = jj[v];
        else u = pp[u], v = pp[v];
    return u;
}

int anc(int u, int dep) {
    while (dd[u] > dep)
        u = (dd[jj[u]] >= dep) ? jj[u] : pp[u];
    return u;
}

struct Query {
    char type[2];
    int a, b;
} qq[N * 2];

/* u = data node, v = ask node */
int query_yesno(int u, int v, int time) {
    if (u == v) return 1;
    int a = lca(u, v);
    int va, ua;
    ua = anc(u, dd[a] + 1);
    va = anc(v, dd[a] + 1);

    if (u == a) {
        return inc[v] - inc[va] == dd[v] - dd[va] && up[v] <= time;
    }
    if (v == a) {
        return inc[u] - inc[ua] == 0 && up[ua] <= time;
    }

    return (dd[v] - dd[va] == inc[v] - inc[va]) && (inc[u] - inc[ua] == 0)
        && up[va] > up[ua] && up[v] <= time;
}

int dp[N], comp[N];

void efs(int u, int time, int root) {
    comp[u] = root;
    for (int j = 0; j < eo[u]; ++j)
        if (fh[u][j] <= time && comp[eh[u][j]] == -1)
            efs(eh[u][j], time, root);
}

int Sq[N], Qs[N];
void build(int ii, int tme) {
    for (int i = 1; i <= n; ++i)
        dp[i] = 1, comp[i] = -1;

    for (int j = ii; j >= 0; --j) {
        int i = Sq[j];
        if (qq[i].type[0] != 'S')
            continue;

        int x = dp[qq[i].a], y = dp[qq[i].b];
        dp[qq[i].a] = max(dp[qq[i].a], y + 1);
        dp[qq[i].b] = max(dp[qq[i].b], x + 1);
    }

    for (int i = 1; i <= n; ++i)
        if (comp[i] == -1)
            efs(i, tme, i);
}

int counted[N];


int main() {
    scanf("%d%d", &n, &q);

    q = n + q - 1;
    for (int j = 0, i = 0; i < q; ++i)
        Qs[i] = -1;
    for (int j = 0, i = 0; i < q; ++i) {
        int a, b = 0;
        char *s = qq[i].type;

        scanf(" %s%d", s, &a);

        if (s[0] == 'S') {
            scanf("%d", &b);
            link(a, b, j);
            Sq[j++] = i;
        } else if (s[0] == 'Q')
            scanf("%d", &b);

        Qs[i] = j;
        qq[i].a = a, qq[i].b = b;
    }

    up[1] = 1e9;
    pp[1] = jj[1] = 1;
    dfs(1, 1);

    build(-1, -1);
    int at = 0;

    for (int j = 0, i = 0; i < q; ++i) {

        if (qq[i].type[0] == 'S')
            ++j;

        if (Qs[i] - at % B == 0) {
            build(Qs[i], j);
            at = Qs[i] + 1;
        }

        if (qq[i].type[0] == 'Q')
            puts(query_yesno(qq[i].b, qq[i].a, j - 1) ? "yes": "no");
        else if (qq[i].type[0] == 'C') {
            int focus = qq[i].a;
            int addition = 0;
            for (int kk = at; kk <= Qs[i]; ++kk) {
                int k = Sq[kk];
                if (qq[k].type[0] == 'S') {
                    int a = qq[k].a, b = qq[k].b;

                    if (counted[a] != i + 1 &&
                            comp[a] != comp[focus] && query_yesno(focus, a, j - 1))
                        ++addition, counted[a] = i + 1;
                    if (counted[b] != i + 1 && 
                            comp[b] != comp[focus] && query_yesno(focus, b, j - 1))
                        ++addition, counted[b] = i + 1;
                }
            }
            printf("%d\n", dp[focus] + addition);
        }

    }
}

Compilation message

servers.c: In function 'pus_':
servers.c:31:26: warning: suggest parentheses around '-' in operand of '&' [-Wparentheses]
   31 |     else if (0 == (o & o - 1)) eh[i] = (int*)realloc(eh[i], 2 * o * sizeof **eh);
      |                        ~~^~~
servers.c: In function 'main':
servers.c:135:14: warning: unused variable 'j' [-Wunused-variable]
  135 |     for (int j = 0, i = 0; i < q; ++i)
      |              ^
servers.c:132:5: warning: ignoring return value of 'scanf' declared with attribute 'warn_unused_result' [-Wunused-result]
  132 |     scanf("%d%d", &n, &q);
      |     ^~~~~~~~~~~~~~~~~~~~~
servers.c:141:9: warning: ignoring return value of 'scanf' declared with attribute 'warn_unused_result' [-Wunused-result]
  141 |         scanf(" %s%d", s, &a);
      |         ^~~~~~~~~~~~~~~~~~~~~
servers.c:144:13: warning: ignoring return value of 'scanf' declared with attribute 'warn_unused_result' [-Wunused-result]
  144 |             scanf("%d", &b);
      |             ^~~~~~~~~~~~~~~
servers.c:148:13: warning: ignoring return value of 'scanf' declared with attribute 'warn_unused_result' [-Wunused-result]
  148 |             scanf("%d", &b);
      |             ^~~~~~~~~~~~~~~

Subtask #1
2.5 / 2.5

# Verdict Execution time Memory Grader output
1 Correct 17 ms 4696 KB Output is correct
2 Correct 42 ms 4352 KB Output is correct
3 Correct 22 ms 4696 KB Output is correct
4 Correct 56 ms 4692 KB Output is correct
5 Correct 43 ms 4688 KB Output is correct
6 Correct 21 ms 5724 KB Output is correct

Subtask #2
0 / 2.5

# Verdict Execution time Memory Grader output
1 Correct 17 ms 4696 KB Output is correct
2 Correct 42 ms 4352 KB Output is correct
3 Correct 22 ms 4696 KB Output is correct
4 Correct 56 ms 4692 KB Output is correct
5 Correct 43 ms 4688 KB Output is correct
6 Correct 21 ms 5724 KB Output is correct
7 Incorrect 18 ms 3540 KB Extra information in the output file
8 Halted 0 ms 0 KB -

Subtask #3
2.5 / 2.5

# Verdict Execution time Memory Grader output
1 Correct 16 ms 4700 KB Output is correct
2 Correct 48 ms 21400 KB Output is correct
3 Correct 50 ms 21328 KB Output is correct

Subtask #4
0 / 2.5

# Verdict Execution time Memory Grader output
1 Correct 16 ms 4700 KB Output is correct
2 Correct 48 ms 21400 KB Output is correct
3 Correct 50 ms 21328 KB Output is correct
4 Incorrect 17 ms 3420 KB Extra information in the output file
5 Halted 0 ms 0 KB -

Subtask #5
5.0 / 5.0

# Verdict Execution time Memory Grader output
1 Correct 21 ms 3416 KB Output is correct
2 Correct 83 ms 30292 KB Output is correct
3 Correct 85 ms 30404 KB Output is correct
4 Correct 91 ms 30240 KB Output is correct

Subtask #6
0 / 5.0

# Verdict Execution time Memory Grader output
1 Correct 21 ms 3416 KB Output is correct
2 Correct 83 ms 30292 KB Output is correct
3 Correct 85 ms 30404 KB Output is correct
4 Correct 91 ms 30240 KB Output is correct
5 Incorrect 16 ms 4696 KB Extra information in the output file
6 Halted 0 ms 0 KB -

Subtask #7
10.0 / 10.0

# Verdict Execution time Memory Grader output
1 Correct 16 ms 3420 KB Output is correct
2 Correct 56 ms 20944 KB Output is correct
3 Correct 64 ms 21016 KB Output is correct

Subtask #8
0 / 10.0

# Verdict Execution time Memory Grader output
1 Correct 16 ms 3420 KB Output is correct
2 Correct 56 ms 20944 KB Output is correct
3 Correct 64 ms 21016 KB Output is correct
4 Incorrect 16 ms 3416 KB Extra information in the output file
5 Halted 0 ms 0 KB -

Subtask #9
12.5 / 12.5

# Verdict Execution time Memory Grader output
1 Correct 18 ms 3416 KB Output is correct
2 Correct 66 ms 30296 KB Output is correct
3 Correct 66 ms 30220 KB Output is correct
4 Correct 101 ms 30208 KB Output is correct
5 Correct 16 ms 4696 KB Output is correct
6 Correct 54 ms 20820 KB Output is correct
7 Correct 58 ms 20816 KB Output is correct
8 Correct 82 ms 21996 KB Output is correct
9 Correct 66 ms 21840 KB Output is correct
10 Correct 74 ms 24520 KB Output is correct
11 Correct 113 ms 23636 KB Output is correct

Subtask #10
0 / 12.5

# Verdict Execution time Memory Grader output
1 Correct 18 ms 3416 KB Output is correct
2 Correct 66 ms 30296 KB Output is correct
3 Correct 66 ms 30220 KB Output is correct
4 Correct 101 ms 30208 KB Output is correct
5 Correct 16 ms 4696 KB Output is correct
6 Correct 54 ms 20820 KB Output is correct
7 Correct 58 ms 20816 KB Output is correct
8 Correct 82 ms 21996 KB Output is correct
9 Correct 66 ms 21840 KB Output is correct
10 Correct 74 ms 24520 KB Output is correct
11 Correct 113 ms 23636 KB Output is correct
12 Incorrect 21 ms 4740 KB Extra information in the output file
13 Halted 0 ms 0 KB -

Subtask #11
17.5 / 17.5

# Verdict Execution time Memory Grader output
1 Correct 16 ms 3416 KB Output is correct
2 Correct 29 ms 4440 KB Output is correct
3 Correct 22 ms 4696 KB Output is correct
4 Correct 45 ms 4692 KB Output is correct
5 Correct 38 ms 4900 KB Output is correct
6 Correct 20 ms 4444 KB Output is correct
7 Correct 16 ms 3512 KB Output is correct
8 Correct 54 ms 21436 KB Output is correct
9 Correct 58 ms 21332 KB Output is correct
10 Correct 19 ms 4700 KB Output is correct
11 Correct 63 ms 30304 KB Output is correct
12 Correct 61 ms 30292 KB Output is correct
13 Correct 86 ms 30288 KB Output is correct
14 Correct 17 ms 4696 KB Output is correct
15 Correct 57 ms 20892 KB Output is correct
16 Correct 65 ms 20824 KB Output is correct
17 Correct 84 ms 21840 KB Output is correct
18 Correct 64 ms 21840 KB Output is correct
19 Correct 71 ms 24404 KB Output is correct
20 Correct 112 ms 23708 KB Output is correct
21 Correct 58 ms 21844 KB Output is correct
22 Correct 55 ms 22000 KB Output is correct
23 Correct 54 ms 22100 KB Output is correct
24 Correct 57 ms 22356 KB Output is correct
25 Correct 77 ms 24120 KB Output is correct
26 Correct 60 ms 21328 KB Output is correct
27 Correct 67 ms 21244 KB Output is correct

Subtask #12
0 / 17.5

# Verdict Execution time Memory Grader output
1 Correct 16 ms 3416 KB Output is correct
2 Correct 29 ms 4440 KB Output is correct
3 Correct 22 ms 4696 KB Output is correct
4 Correct 45 ms 4692 KB Output is correct
5 Correct 38 ms 4900 KB Output is correct
6 Correct 20 ms 4444 KB Output is correct
7 Correct 16 ms 3512 KB Output is correct
8 Correct 54 ms 21436 KB Output is correct
9 Correct 58 ms 21332 KB Output is correct
10 Correct 19 ms 4700 KB Output is correct
11 Correct 63 ms 30304 KB Output is correct
12 Correct 61 ms 30292 KB Output is correct
13 Correct 86 ms 30288 KB Output is correct
14 Correct 17 ms 4696 KB Output is correct
15 Correct 57 ms 20892 KB Output is correct
16 Correct 65 ms 20824 KB Output is correct
17 Correct 84 ms 21840 KB Output is correct
18 Correct 64 ms 21840 KB Output is correct
19 Correct 71 ms 24404 KB Output is correct
20 Correct 112 ms 23708 KB Output is correct
21 Correct 58 ms 21844 KB Output is correct
22 Correct 55 ms 22000 KB Output is correct
23 Correct 54 ms 22100 KB Output is correct
24 Correct 57 ms 22356 KB Output is correct
25 Correct 77 ms 24120 KB Output is correct
26 Correct 60 ms 21328 KB Output is correct
27 Correct 67 ms 21244 KB Output is correct
28 Incorrect 16 ms 4700 KB Extra information in the output file
29 Halted 0 ms 0 KB -