Submission #256336

#	Time	Username	Problem	Language	Result	Execution time	Memory
256336		uacoder123	Biochips (IZhO12_biochips)	C++14	100 / 100	498 ms	405880 KiB

biochips

#include <bits/stdc++.h>
#include <ext/pb_ds/assoc_container.hpp>
using namespace std;
using namespace __gnu_pbds;
#define F first
#define S second
#define FOR(i,a,b) for (auto i = (a); i <= (b); ++i)
#define NFOR(i,a,b) for(auto i = (a); i >= (b); --i)
#define all(x) (x).begin(), (x).end()
#define sz(x) int(x.size())
#define mp(i,a) make_pair(i,a)
#define pb(a) push_back(a)
#define bit(x,b) (x&(1LL<<b))

typedef  long long int lli;
typedef pair <lli,lli> ii;
typedef pair <lli,ii> iii;
typedef vector <lli> vi;
typedef tree<int,null_type,less<int>,rb_tree_tag,tree_order_statistics_node_update> ordered_set;
int arr[200001][501]={};
int n,m;
vi al[200001];
int val[200001];
int dp[501]={};
void dfs(int node,int p)
{
  for(int i=1;i<=m;++i)
  {
    if(dp[i-1]==-1)
    {
      arr[node][i]=-1;
      continue;
    }
    arr[node][i]=dp[i-1]+val[node];
  }
  for(int i=0;i<al[node].size();++i)
    if(al[node][i]!=p)
      dfs(al[node][i],node);
  for(int i=1;i<=m;++i)
    dp[i]=max(dp[i],arr[node][i]);
}
int main()
{
  ios_base::sync_with_stdio(false);
  cin.tie(NULL);
  cin>>n>>m;
  int r;
  for(int i=1;i<=m;++i)
    dp[i]=-1;
  for(int i=1;i<=n;++i)
  {
    int f,w;
    cin>>f>>w;
    if(f!=0)
    {
      al[f].pb(i);
      al[i].pb(f);
    }
    else
      r=i;
    val[i]=w;
  }
  dfs(r,r);
  cout<<dp[m]<<endl;
  return(0);
}

Compilation message (stderr)

biochips.cpp: In function 'void dfs(int, int)':
biochips.cpp:36:16: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
   for(int i=0;i<al[node].size();++i)
               ~^~~~~~~~~~~~~~~~
biochips.cpp: In function 'int main()':
biochips.cpp:63:6: warning: 'r' may be used uninitialized in this function [-Wmaybe-uninitialized]
   dfs(r,r);
   ~~~^~~~~

• Subtask 1: 100 / 100