Submission #986414

#	Time	Username	Problem	Language	Result	Execution time	Memory
986414		Neco_arc	Cat in a tree (BOI17_catinatree)	C++17	51 / 100	1032 ms	154040 KiB

catinatree

#include <bits/stdc++.h>
//#include <bits/debug.hpp>

#define ll long long
#define all(x) x.begin(), x.end()
#define Neco "Maximum Weight Subset"
#define resp(x) sort(all(x)), x.resize(unique(all(x)) - x.begin())
#define getbit(x,i) ((x >> i)&1)
#define _left id * 2, l, mid
#define _right id * 2 + 1, mid + 1, r
#define cntbit(x) __builtin_popcountll(x)
#define fi(i, a, b) for(int i = a; i <= b; i++)
#define fid(i, a, b) for(int i = a; i >= b; i--)
#define maxn (int) 2e5 + 7

using namespace std;

const ll mod = 1e9 + 7; //972663749
const ll base = 911382323;

int n, k;
vector<int> edges[maxn];
deque<int> dp[maxn];

deque<int> cb(const deque<int> &a, const deque<int> &b) {
    deque<int> ans(a.size() + b.size() - 1, -1e9);
    fi(i, 0, a.size() - 1) fi(j, 0, b.size() - 1) {
        if(i + j >= k) ans[min(i, j)] = max(ans[min(i, j)], a[i] + b[j]);
    }
    fi(i, 0, b.size() - 1) ans[i] = max(ans[i], b[i]);
    fi(i, 0, a.size() - 1) ans[i] = max(ans[i], a[i]);
    return ans;
}

void dfs(int u, int par) {
    dp[u] = {1};
    for(int v : edges[u]) if(v != par) {
        dfs(v, u);
        dp[u] = cb(dp[u], dp[v]);
    }

    dp[u].push_front(-1e9);
}

void solve()
{

    cin >> n >> k;
    fi(i, 2, n) {
        int x; cin >> x, ++x;
        edges[x].push_back(i);
    }

    dfs(1, 0);
    cout << *max_element(all(dp[1]));


}


int main()
{

    ios_base::sync_with_stdio(0);
    cin.tie(0);
    cout.tie(0);

    if(fopen(Neco".inp", "r")) {
        freopen(Neco".inp", "r", stdin);
        freopen(Neco".out", "w", stdout);
    }


    int nTest = 1;
//    cin >> nTest;


    while(nTest--)
    {
        solve();
    }


    return 0;
}

Compilation message (stderr)

catinatree.cpp: In function 'std::deque<int> cb(const std::deque<int>&, const std::deque<int>&)':
catinatree.cpp:12:38: warning: comparison of integer expressions of different signedness: 'int' and 'std::deque<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   12 | #define fi(i, a, b) for(int i = a; i <= b; i++)
......
   27 |     fi(i, 0, a.size() - 1) fi(j, 0, b.size() - 1) {
      |        ~~~~~~~~~~~~~~~~~~             
catinatree.cpp:27:5: note: in expansion of macro 'fi'
   27 |     fi(i, 0, a.size() - 1) fi(j, 0, b.size() - 1) {
      |     ^~
catinatree.cpp:12:38: warning: comparison of integer expressions of different signedness: 'int' and 'std::deque<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   12 | #define fi(i, a, b) for(int i = a; i <= b; i++)
......
   27 |     fi(i, 0, a.size() - 1) fi(j, 0, b.size() - 1) {
      |                               ~~~~~~~~~~~~~~~~~~
catinatree.cpp:27:28: note: in expansion of macro 'fi'
   27 |     fi(i, 0, a.size() - 1) fi(j, 0, b.size() - 1) {
      |                            ^~
catinatree.cpp:12:38: warning: comparison of integer expressions of different signedness: 'int' and 'std::deque<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   12 | #define fi(i, a, b) for(int i = a; i <= b; i++)
......
   30 |     fi(i, 0, b.size() - 1) ans[i] = max(ans[i], b[i]);
      |        ~~~~~~~~~~~~~~~~~~             
catinatree.cpp:30:5: note: in expansion of macro 'fi'
   30 |     fi(i, 0, b.size() - 1) ans[i] = max(ans[i], b[i]);
      |     ^~
catinatree.cpp:12:38: warning: comparison of integer expressions of different signedness: 'int' and 'std::deque<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   12 | #define fi(i, a, b) for(int i = a; i <= b; i++)
......
   31 |     fi(i, 0, a.size() - 1) ans[i] = max(ans[i], a[i]);
      |        ~~~~~~~~~~~~~~~~~~             
catinatree.cpp:31:5: note: in expansion of macro 'fi'
   31 |     fi(i, 0, a.size() - 1) ans[i] = max(ans[i], a[i]);
      |     ^~
catinatree.cpp: In function 'int main()':
catinatree.cpp:69:16: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
   69 |         freopen(Neco".inp", "r", stdin);
      |         ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~
catinatree.cpp:70:16: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
   70 |         freopen(Neco".out", "w", stdout);
      |         ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~

• Subtask 1: 11 / 11
• Subtask 2: 40 / 40
• Subtask 3: 0 / 49