Cod sursa(job #1637491)

Utilizator TimitocArdelean Andrei Timotei Timitoc Data 7 martie 2016 17:41:55
Problema Arbore Scor 45
Compilator cpp Status done
Runda Arhiva de probleme Marime 1.21 kb
#include <iostream>
#include <cstdio>
#include <vector>
#define MAXN 100050

using namespace std;

vector<int> graf[MAXN];
int parent[MAXN], n, m, nq;
int val[MAXN], liniar[MAXN], first[MAXN], last[MAXN];

void citire()
{
	scanf("%d %d", &n, &m);
	for (int i = 1; i <= n-1; i++) {
		int x, y;
		scanf("%d %d", &x, &y);
        graf[x].push_back(y);
        graf[y].push_back(x);
	}
}

void dfs(int nod = 1)
{
	liniar[++nq] = nod;
	first[nod] = nq;
	for (const auto& y : graf[nod])
        if (!parent[y]) {
			parent[y] = nod;
			dfs(y);
			//liniar[++nq] = nod;
        }
	last[nod] = nq;
}

void update(int x, int sum)
{
	val[first[x]] += sum;
	val[last[x]+1] -= sum;
}

int get(int sum)
{
    int rez = 0;
    for (int i = 1; i <= 2*n-1; i++) {
		rez += val[i];
        if (rez == sum)
            return liniar[i];
    }
    return -1;
}

int main()
{
	freopen("arbore.in", "r", stdin);
	freopen("arbore.out", "w", stdout);

    citire();
    parent[1] = 1;
	dfs();
	for (int i = 1; i <= m; i++) {
		int tip, x, y;
        scanf("%d ", &tip);
        if (tip == 1) {
			scanf("%d %d", &x, &y);
            update(x, y);
        }
        else {
			scanf("%d", &x);
            printf("%d\n", get(x));
        }
	}

    return 0;
}