Submission #966516

#	Time	Username	Problem	Language	Result	Execution time	Memory
966516		steveonalex	Fireworks (APIO16_fireworks)	C++17	100 / 100	181 ms	101456 KiB

fireworks

#include <bits/stdc++.h>
 
using namespace std;
 
typedef long long ll;
typedef unsigned long long ull;
 
#define ALL(v) (v).begin(), (v).end()
#define MASK(i) (1LL << (i))
#define GETBIT(mask, i) (((mask) >> (i)) & 1)
 
// mt19937_64 rng(chrono::steady_clock::now().time_since_epoch().count());
mt19937_64 rng(1);
ll rngesus(ll l, ll r){return ((ull) rng()) % (r - l + 1) + l;}
 
ll max(ll a, ll b){return (a > b) ? a : b;}
ll min(ll a, ll b){return (a < b) ? a : b;}
 
ll LASTBIT(ll mask){return mask & (-mask);}
ll pop_cnt(ll mask){return __builtin_popcountll(mask);}
ll ctz(ll mask){return __builtin_ctzll(mask);}
ll clz(ll mask){return __builtin_clzll(mask);}
ll logOf(ll mask){return 63 - clz(mask);}
 
template <class T1, class T2>
    bool minimize(T1 &a, T2 b){
        if (a > b){a = b; return true;}
        return false;
    }
template <class T1, class T2>
    bool maximize(T1 &a, T2 b){
        if (a < b){a = b; return true;}
        return false;
    }
template <class T>
    void printArr(T& a, string separator = " ", string finish = "\n", ostream& out = cout){
        for(auto i: a) out << i << separator;
        out << finish;
    }
template <class T>
    void remove_dup(vector<T> &a){
        sort(ALL(a));
        a.resize(unique(ALL(a)) - a.begin());
    }

struct SlopeTrick{
    ll coeff, init_slope;
    priority_queue<ll> slope_point;

    SlopeTrick(){
        init_slope = 0;
        coeff = 0;
    }
};

const int N = 3e5 + 69;
const ll INF = 1e18 + 69;
int n, m;
vector<pair<int,int>> graph[N];
SlopeTrick dp[N];

void dfs(int u){
    if (u > n){
        return;
    }
    for(pair<int, int> v: graph[u]){
        dfs(v.first);
        SlopeTrick child_slope;
        if (v.first > n){
            child_slope.coeff = v.second;
            child_slope.init_slope = -1;
            child_slope.slope_point.push(v.second);
            child_slope.slope_point.push(v.second);
        }
        else{
            swap(child_slope, dp[v.first]);
            child_slope.coeff += v.second;
            ll x = child_slope.slope_point.top(); child_slope.slope_point.pop();
            ll y = child_slope.slope_point.top(); child_slope.slope_point.pop();
            child_slope.slope_point.push(x + v.second);
            child_slope.slope_point.push(y + v.second);
        }

        dp[u].coeff += child_slope.coeff;
        dp[u].init_slope += child_slope.init_slope;
        if (child_slope.slope_point.size() > dp[u].slope_point.size()) 
            swap(child_slope.slope_point, dp[u].slope_point);
        while(child_slope.slope_point.size()){
            dp[u].slope_point.push(child_slope.slope_point.top());
            child_slope.slope_point.pop();
        }
    }
    while(dp[u].slope_point.size() > (1 - dp[u].init_slope)) dp[u].slope_point.pop();
}

int main(void){
    ios::sync_with_stdio(0); cin.tie(0); cout.tie(0);

    cin >> n >> m;
    for(int i = 2; i<=n+m; ++i){
        int p, c; cin >> p >> c;
        graph[p].push_back({i, c});
    }

    dfs(1);

    SlopeTrick ans = dp[1];
    ll x = ans.coeff;
    ll slope = ans.init_slope;

    vector<ll> slope_point;
    while(ans.slope_point.size()) {
        slope_point.push_back(ans.slope_point.top());
        ans.slope_point.pop();
    }
    slope_point.push_back(0);
    reverse(ALL(slope_point));
    for(int i = 1; i<slope_point.size(); ++i){
        ll dx = slope_point[i] - slope_point[i-1];
        x += slope * dx;
        slope++;
        if (slope == 0) break;
    }
    cout << x << "\n";

    // for(int i = 0; i<N; ++i) minimize(ans, dp[1][i]);
    // const int N = 41;
    // int f[N], g[N], c[N];
    // for(int i = 0; i<N; ++i) f[i] = abs(i-13) + abs(i-7);
    // for(int i = 0; i<N; ++i) g[i] = abs(i - 3);

    // memset(c, 63, sizeof c);
    // for(int i = 0; i<N; ++i) for(int j = 0; i + j < N; ++j) 
    //     minimize(c[i + j], g[i] + f[j]);
    // for(int i= 0; i<N; ++i) cout << c[i] << " "; cout << "\n";

    return 0;
}

Compilation message (stderr)

fireworks.cpp: In function 'void dfs(int)':
fireworks.cpp:93:36: warning: comparison of integer expressions of different signedness: 'std::priority_queue<long long int>::size_type' {aka 'long unsigned int'} and 'll' {aka 'long long int'} [-Wsign-compare]
   93 |     while(dp[u].slope_point.size() > (1 - dp[u].init_slope)) dp[u].slope_point.pop();
      |           ~~~~~~~~~~~~~~~~~~~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~
fireworks.cpp: In function 'int main()':
fireworks.cpp:118:21: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<long long int, std::allocator<long long int> >::size_type' {aka 'long unsigned int'} [-Wsign-compare]
  118 |     for(int i = 1; i<slope_point.size(); ++i){
      |                    ~^~~~~~~~~~~~~~~~~~~

• Subtask 1: 7 / 7
• Subtask 2: 19 / 19
• Subtask 3: 29 / 29
• Subtask 4: 45 / 45