Submission #172694

#	Time	Username	Problem	Language	Result	Execution time	Memory
172694		rzbt	Cat in a tree (BOI17_catinatree)	C++14	100 / 100	116 ms	15712 KiB

catinatree

#include <bits/stdc++.h>
#define mp make_pair
#define pb push_back
#define F first
#define S second
#define all(x) x.begin(),x.end()
#define MAXN 200005
typedef long long ll;


using namespace std;

int dp[MAXN],udalj[MAXN];
int n,k;
vector<int> graf[MAXN];

void dfs(int t){
    if(graf[t].empty()){
        dp[t]=1;
        udalj[t]=0;
        return;
    }
    dfs(graf[t][0]);
    udalj[t]=udalj[graf[t][0]]+1;
    dp[t]=dp[graf[t][0]];
    if(udalj[t]==k){
        udalj[t]=0;
        dp[t]++;
    }
    bool prvi=true;
    for(auto x:graf[t]){
        if(prvi){
            prvi=false;
            continue;
        }
        dfs(x);
        if(udalj[t]+udalj[x]+1>=k){
            dp[t]+=dp[x];
            udalj[t]=min(udalj[t],udalj[x]+1);
        }else{
            dp[t]+=dp[x]-1;
            udalj[t]=max(udalj[t],udalj[x]+1);
        }
    }
    //printf("%d  %d %d",t,udalj[t],dp[t]);

}



int main()
{
    scanf("%d %d", &n, &k);
    for(int i=1;i<n;i++){
        int t;
        scanf("%d", &t);
        graf[t].pb(i);
    }
    dfs(0);
    printf("%d",dp[0]);
    return 0;
}

Compilation message (stderr)

catinatree.cpp: In function 'int main()':
catinatree.cpp:53:10: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
     scanf("%d %d", &n, &k);
     ~~~~~^~~~~~~~~~~~~~~~~
catinatree.cpp:56:14: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
         scanf("%d", &t);
         ~~~~~^~~~~~~~~~

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