Submission #165679

#	Time	Username	Problem	Language	Result	Execution time	Memory
165679		nvmdava	Regions (IOI09_regions)	C++17	100 / 100	4334 ms	34904 KiB

regions

#include <bits/stdc++.h>
using namespace std;
#define ff first
#define ss second
mt19937 rng(chrono::steady_clock::now().time_since_epoch().count());
#define N 200005

int h[N], p[N], ho[N], le[N], ri[N], cntr;

int rs[25005];
vector<int> rid[25005], ch[N];
vector<pair<pair<int, int>, int> > rra[25005];

void dfs(int v){
    int t = ++cntr;
    rid[h[v]].push_back(cntr);
    ho[cntr] = h[v];
    for(auto& x : ch[v])
        dfs(x);
    ri[t] = cntr;
}

map<int, int> dif, cache;

void addrange(int v){
    dif.clear();
    for(auto& x : rid[v]){
        ++dif[x];
        --dif[ri[x] + 1];
    }

    int now = 0, le = -1;

    for(auto& x : dif){
        if(now != 0){
            rra[v].push_back({{le, x.ff - 1}, now});
        }
        now += x.ss;
        le = x.ff;
    }
}


int main(){
    int n, r, q;
    scanf("%d%d%d%d", &n, &r, &q, &h[1]);
    ++rs[h[1]];
    for(int i = 2; i <= n; ++i){
        scanf("%d%d", &p[i], &h[i]);
        ++rs[h[i]];
        ch[p[i]].push_back(i);
    }

    dfs(1);
    cntr = 0;
    for(int i = 1; i <= r; ++i)
        addrange(i);
    


    while(q--){
        int r1, r2;
        scanf("%d%d", &r1, &r2);
        auto it = cache.find(r1 * 25000 + r2);
        if(it != cache.end()){
            printf("%d\n", it -> ss);
            fflush(stdout);
            continue;
        }
        int ans = 0, i = 0;
        for(auto& x : rid[r2]){
            while(rra[r1].size() > i && rra[r1][i].ff.ss < x)
                ++i;
            if(rra[r1].size() == i)
                break;
            if(rra[r1].size() != i && rra[r1][i].ff.ff <= x)
                ans += rra[r1][i].ss;
        }
        cache[r1 * 25000 + r2] = ans;
        printf("%d\n", ans);
        fflush(stdout);
    }
}

Compilation message (stderr)

regions.cpp: In function 'int main()':
regions.cpp:72:34: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
             while(rra[r1].size() > i && rra[r1][i].ff.ss < x)
                   ~~~~~~~~~~~~~~~^~~
regions.cpp:74:31: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
             if(rra[r1].size() == i)
                ~~~~~~~~~~~~~~~^~~~
regions.cpp:76:31: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
             if(rra[r1].size() != i && rra[r1][i].ff.ff <= x)
                ~~~~~~~~~~~~~~~^~~~
regions.cpp:46:10: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
     scanf("%d%d%d%d", &n, &r, &q, &h[1]);
     ~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
regions.cpp:49:14: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
         scanf("%d%d", &p[i], &h[i]);
         ~~~~~^~~~~~~~~~~~~~~~~~~~~~
regions.cpp:63:14: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
         scanf("%d%d", &r1, &r2);
         ~~~~~^~~~~~~~~~~~~~~~~~

• Subtask 1: 15 / 15
• Subtask 2: 85 / 85