Submission #355424

# Submission time Handle Problem Language Result Execution time Memory
355424 2021-01-22T13:03:09 Z spatarel Cat in a tree (BOI17_catinatree) C++17
11 / 100
278 ms 283372 KB
#include <stdio.h>
#include <algorithm>
#include <deque>
#include <vector>

const int MAX_N = 200000;

int N, D;
std::vector<int> children[MAX_N];

std::deque<int> maxN[MAX_N];
int depth[MAX_N];

void dfs(int u) {
  depth[u] = 1;
  int deepestChild = -1;
  int secondDepth = 0;
  for (int v : children[u]) {
    dfs(v);
    if (depth[u] <= 1 + depth[v]) {
      secondDepth = depth[u];
      depth[u] = 1 + depth[v];
      deepestChild = v;
    } else if (secondDepth < 1 + depth[v]) {
      secondDepth = 1 + depth[v];
    }
  }
  if (secondDepth >= D / 2) {
    maxN[u] = std::deque<int>(1 + D);
    maxN[u][0] = 1;
    for (int v : children[u]) {
      if (depth[v] > D - 1) {
        maxN[u][0] += maxN[v][D - 1];
      }
    }
    std::vector<int> maxAdd(1 + D);
    for (int v : children[u]) {
      for (int d = 0; d < D && d < depth[v]; d++) {
        maxN[u][d + 1] += maxN[v][d];
      }
      for (int d = 0; d < D - d - 2 && d < depth[v]; d++) {
        maxAdd[d + 1] = std::max(maxAdd[d + 1],
            maxN[v][d] - maxN[v][D - d - 2]);
      }
    }
    for (int d = 0; d < D - d - 2; d++) {
      maxN[u][d + 1] = maxAdd[d + 1] + maxN[u][D - d - 1];
    }
    for (int d = D - 1; d >= 1; d--) {
      maxN[u][d - 1] = std::max(maxN[u][d - 1], maxN[u][d]);
    }
  } else {
    //printf("u = %d\n", u);
    //printf("second depth = %d\n", secondDepth);
    //fflush(stdout);
    std::vector<int> maxAdd(secondDepth);
    //printf("second depth = %d\n", secondDepth);
    //fflush(stdout);
    for (int v : children[u]) {
      for (int d = 0; d < D - d - 2 && d < depth[v]; d++) {
        maxAdd[d + 1] = std::max(maxAdd[d + 1],
            maxN[v][d] /* - maxN[v][D - d - 2] */);
      }
    }
    if (deepestChild != -1) {
      std::swap(maxN[u], maxN[deepestChild]);
    }
    //printf("mama\n");
    //fflush(stdout);
    maxN[u].push_front(0);
    //printf("tata\n");
    //fflush(stdout);
    maxN[u][0] = 1;
    for (int v : children[u]) {
      //printf("v = %d\n", v);
      //fflush(stdout);
      if (depth[v] > D - 1) {
        maxN[u][0] += maxN[v][D - 1];
      }
    }
    for (int v : children[u]) {
      if (v != deepestChild) {
        for (int d = 0; d < D && d < depth[v]; d++) {
          maxN[u][d + 1] += maxN[v][d];
        }
      }
    }
    for (int d = 0; d + 1 < secondDepth; d++) {
      maxN[u][d + 1] = maxAdd[d + 1] /* + maxN[u][D - d - 1] */;
    }
    for (int d = secondDepth; d >= 1; d--) {
      maxN[u][d - 1] = std::max(maxN[u][d - 1], maxN[u][d]);
    }
  }
  /*
  printf("maxN[%d] = {", u);
  for (int d = 0; d < D; d++) {
    printf("%d, ", maxN[u][d]);
  }
  printf("}\n");
  fflush(stdout);//*/
}

int main() {
  scanf("%d%d", &N, &D);
  for (int i = 1; i < N; i++) {
    int xi;
    scanf("%d", &xi);
    children[xi].push_back(i);
  }
  dfs(0);
  int answer = maxN[0][0];
  printf("%d\n", answer);
  return 0;
}

Compilation message

catinatree.cpp: In function 'int main()':
catinatree.cpp:105:8: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
  105 |   scanf("%d%d", &N, &D);
      |   ~~~~~^~~~~~~~~~~~~~~~
catinatree.cpp:108:10: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
  108 |     scanf("%d", &xi);
      |     ~~~~~^~~~~~~~~~~
# Verdict Execution time Memory Grader output
1 Correct 109 ms 139628 KB Output is correct
2 Correct 108 ms 139708 KB Output is correct
3 Correct 110 ms 139628 KB Output is correct
4 Correct 108 ms 139628 KB Output is correct
5 Correct 109 ms 139628 KB Output is correct
6 Correct 113 ms 139756 KB Output is correct
7 Correct 110 ms 139628 KB Output is correct
8 Correct 110 ms 139884 KB Output is correct
9 Correct 111 ms 139628 KB Output is correct
10 Correct 110 ms 139628 KB Output is correct
11 Correct 108 ms 139628 KB Output is correct
12 Correct 110 ms 139756 KB Output is correct
13 Correct 109 ms 139628 KB Output is correct
14 Correct 110 ms 139600 KB Output is correct
15 Correct 108 ms 139628 KB Output is correct
16 Correct 108 ms 139628 KB Output is correct
17 Correct 110 ms 139628 KB Output is correct
18 Correct 111 ms 139792 KB Output is correct
19 Correct 110 ms 139628 KB Output is correct
20 Correct 108 ms 139628 KB Output is correct
# Verdict Execution time Memory Grader output
1 Correct 109 ms 139628 KB Output is correct
2 Correct 108 ms 139708 KB Output is correct
3 Correct 110 ms 139628 KB Output is correct
4 Correct 108 ms 139628 KB Output is correct
5 Correct 109 ms 139628 KB Output is correct
6 Correct 113 ms 139756 KB Output is correct
7 Correct 110 ms 139628 KB Output is correct
8 Correct 110 ms 139884 KB Output is correct
9 Correct 111 ms 139628 KB Output is correct
10 Correct 110 ms 139628 KB Output is correct
11 Correct 108 ms 139628 KB Output is correct
12 Correct 110 ms 139756 KB Output is correct
13 Correct 109 ms 139628 KB Output is correct
14 Correct 110 ms 139600 KB Output is correct
15 Correct 108 ms 139628 KB Output is correct
16 Correct 108 ms 139628 KB Output is correct
17 Correct 110 ms 139628 KB Output is correct
18 Correct 111 ms 139792 KB Output is correct
19 Correct 110 ms 139628 KB Output is correct
20 Correct 108 ms 139628 KB Output is correct
21 Runtime error 278 ms 283372 KB Execution killed with signal 11
22 Halted 0 ms 0 KB -
# Verdict Execution time Memory Grader output
1 Correct 109 ms 139628 KB Output is correct
2 Correct 108 ms 139708 KB Output is correct
3 Correct 110 ms 139628 KB Output is correct
4 Correct 108 ms 139628 KB Output is correct
5 Correct 109 ms 139628 KB Output is correct
6 Correct 113 ms 139756 KB Output is correct
7 Correct 110 ms 139628 KB Output is correct
8 Correct 110 ms 139884 KB Output is correct
9 Correct 111 ms 139628 KB Output is correct
10 Correct 110 ms 139628 KB Output is correct
11 Correct 108 ms 139628 KB Output is correct
12 Correct 110 ms 139756 KB Output is correct
13 Correct 109 ms 139628 KB Output is correct
14 Correct 110 ms 139600 KB Output is correct
15 Correct 108 ms 139628 KB Output is correct
16 Correct 108 ms 139628 KB Output is correct
17 Correct 110 ms 139628 KB Output is correct
18 Correct 111 ms 139792 KB Output is correct
19 Correct 110 ms 139628 KB Output is correct
20 Correct 108 ms 139628 KB Output is correct
21 Runtime error 278 ms 283372 KB Execution killed with signal 11
22 Halted 0 ms 0 KB -