Submission #355440

# Submission time Handle Problem Language Result Execution time Memory
355440 2021-01-22T13:31:45 Z spatarel Cat in a tree (BOI17_catinatree) C++17
11 / 100
262 ms 283400 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] - (D - d - 2 < depth[v] ? maxN[v][D - d - 2] : 0));
      }
    }
    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);
    //fflush(stdout);
    std::vector<int> maxAdd(secondDepth + 1);
    //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 + 1 <= secondDepth; d++) {
        maxAdd[d + 1] = std::max(maxAdd[d + 1],
            maxN[v][d] /* - maxN[v][D - d - 2] */);
      }
    }
    //printf("tata\n");
    //fflush(stdout);
    if (deepestChild != -1) {
      std::swap(maxN[u], maxN[deepestChild]);
    }
    //printf("mama\n");
    //fflush(stdout);
    maxN[u].push_front(0);
    maxN[u][0] = 1;
    for (int v : children[u]) {
      if (depth[v] > D - 1) {
        maxN[u][0] += maxN[v][D - 1];
      }
    }
    //printf("maxN[u][0] = %d\n", maxN[u][0]);
    //fflush(stdout);
    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 + 1; 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 < depth[u]; 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:104:8: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
  104 |   scanf("%d%d", &N, &D);
      |   ~~~~~^~~~~~~~~~~~~~~~
catinatree.cpp:107:10: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
  107 |     scanf("%d", &xi);
      |     ~~~~~^~~~~~~~~~~
# Verdict Execution time Memory Grader output
1 Correct 114 ms 139692 KB Output is correct
2 Correct 107 ms 139628 KB Output is correct
3 Correct 107 ms 139776 KB Output is correct
4 Correct 110 ms 139628 KB Output is correct
5 Correct 116 ms 139756 KB Output is correct
6 Correct 109 ms 139628 KB Output is correct
7 Correct 108 ms 139628 KB Output is correct
8 Correct 108 ms 139628 KB Output is correct
9 Correct 108 ms 139628 KB Output is correct
10 Correct 111 ms 139756 KB Output is correct
11 Correct 108 ms 139628 KB Output is correct
12 Correct 108 ms 139628 KB Output is correct
13 Correct 121 ms 139628 KB Output is correct
14 Correct 109 ms 139680 KB Output is correct
15 Correct 109 ms 139628 KB Output is correct
16 Correct 108 ms 139628 KB Output is correct
17 Correct 107 ms 139680 KB Output is correct
18 Correct 108 ms 139628 KB Output is correct
19 Correct 121 ms 139668 KB Output is correct
20 Correct 107 ms 139628 KB Output is correct
# Verdict Execution time Memory Grader output
1 Correct 114 ms 139692 KB Output is correct
2 Correct 107 ms 139628 KB Output is correct
3 Correct 107 ms 139776 KB Output is correct
4 Correct 110 ms 139628 KB Output is correct
5 Correct 116 ms 139756 KB Output is correct
6 Correct 109 ms 139628 KB Output is correct
7 Correct 108 ms 139628 KB Output is correct
8 Correct 108 ms 139628 KB Output is correct
9 Correct 108 ms 139628 KB Output is correct
10 Correct 111 ms 139756 KB Output is correct
11 Correct 108 ms 139628 KB Output is correct
12 Correct 108 ms 139628 KB Output is correct
13 Correct 121 ms 139628 KB Output is correct
14 Correct 109 ms 139680 KB Output is correct
15 Correct 109 ms 139628 KB Output is correct
16 Correct 108 ms 139628 KB Output is correct
17 Correct 107 ms 139680 KB Output is correct
18 Correct 108 ms 139628 KB Output is correct
19 Correct 121 ms 139668 KB Output is correct
20 Correct 107 ms 139628 KB Output is correct
21 Runtime error 262 ms 283400 KB Execution killed with signal 11
22 Halted 0 ms 0 KB -
# Verdict Execution time Memory Grader output
1 Correct 114 ms 139692 KB Output is correct
2 Correct 107 ms 139628 KB Output is correct
3 Correct 107 ms 139776 KB Output is correct
4 Correct 110 ms 139628 KB Output is correct
5 Correct 116 ms 139756 KB Output is correct
6 Correct 109 ms 139628 KB Output is correct
7 Correct 108 ms 139628 KB Output is correct
8 Correct 108 ms 139628 KB Output is correct
9 Correct 108 ms 139628 KB Output is correct
10 Correct 111 ms 139756 KB Output is correct
11 Correct 108 ms 139628 KB Output is correct
12 Correct 108 ms 139628 KB Output is correct
13 Correct 121 ms 139628 KB Output is correct
14 Correct 109 ms 139680 KB Output is correct
15 Correct 109 ms 139628 KB Output is correct
16 Correct 108 ms 139628 KB Output is correct
17 Correct 107 ms 139680 KB Output is correct
18 Correct 108 ms 139628 KB Output is correct
19 Correct 121 ms 139668 KB Output is correct
20 Correct 107 ms 139628 KB Output is correct
21 Runtime error 262 ms 283400 KB Execution killed with signal 11
22 Halted 0 ms 0 KB -