Submission #521672

#	Time	Username	Problem	Language	Result	Execution time	Memory
521672		idas	Tax Evasion (LMIO19_mokesciai)	C++11	100 / 100	395 ms	46380 KiB

mokesciai

#include <bits/stdc++.h>
#define FOR(i, begin, end) for(int i = (begin); i < (end); i++)
#define FAST_IO ios_base::sync_with_stdio(0); cin.tie(nullptr); cout.tie(nullptr)
#define f first
#define s second
#define pb push_back
#define sz(x) ((int)((x).size()))
#define le(vec) vec[vec.size()-1]
#define all(x) (x).begin(), (x).end()
#define TSTS int ttt; cin >> ttt; while(ttt--) solve()

using namespace std;
typedef long long ll;
typedef vector<int> vi;
typedef long double ld;
typedef map<int, int> mii;
typedef pair<int, int> pii;
typedef pair<long long, long long> pll;
typedef pair<long double, long double> pdd;

const int INF=1e9, MOD=1e9+7, mod=998244353;
const ll LINF=1e18;

void setIO()
{
    FAST_IO;
}

void setIO(string s)
{
    FAST_IO;
    freopen((s+".in").c_str(), "r", stdin);
    freopen((s+".out").c_str(), "w", stdout);
}

const int N=2e5+10, L=19;
int n, m, par[N][L], dp[N], dol[N];
vi ad[N], dollas;

void pre(int u, int pst)
{
    for(auto x : ad[u]){
        if(x==pst) continue;
        dp[x]=dp[u]+1;
        par[x][0]=u;
        pre(x, u);
    }
}

void build()
{
    FOR(i, 1, L)
    {
        FOR(j, 0, n)
        {
            par[j][i]=par[par[j][i-1]][i-1];
        }
    }
}

int lift(int u, int d)
{
    for(int i=L-1; i>=0; i--){
        if(d&(1<<i))
        u=par[u][i];
    }
    return u;
}

void place()
{
    for(auto x : dollas){
        dol[lift(x, (dp[x]-1)/2)]++;
    }
}

bool ok;
int tr(int u, int pst, int x)
{
    int tot=0;
    for(auto v : ad[u]){
        if(v==pst) continue;
        tot+=tr(v, u, x);
    }
    if(dp[u]>=x) tot++;
    if(tot<dol[u]) ok=false;
    tot-=dol[u];
    return tot;
}

bool can(int x)
{
    ok=true;
    tr(0,-1,x);
    return ok;
}

int main()
{
    setIO();
    cin >> n >> m;
    FOR(i, 0, n-1)
    {
        int x; cin >> x;
        ad[x-1].pb(i+1);
        ad[i+1].pb(x-1);
    }
    FOR(i, 0, m)
    {
        int x; cin >> x;
        dollas.pb(x-1);
    }

    pre(0,-1);
    build();
    place();

    int l=0, r=n;
    while(l<r){
        int m=(l+r+1)/2;
        if(can(m)) l=m;
        else r=m-1;
    }

    cout << l+1;
}

Compilation message (stderr)

mokesciai.cpp: In function 'void setIO(std::string)':
mokesciai.cpp:32:12: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
   32 |     freopen((s+".in").c_str(), "r", stdin);
      |     ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
mokesciai.cpp:33:12: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
   33 |     freopen((s+".out").c_str(), "w", stdout);
      |     ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

• Subtask 1: 10 / 10
• Subtask 2: 22 / 22
• Subtask 3: 39 / 39
• Subtask 4: 29 / 29