Submission #40443

#	Time	Username	Problem	Language	Result	Execution time	Memory
40443		szawinis	Birthday gift (IZhO18_treearray)	C++14	100 / 100	2045 ms	105188 KiB

treearray

#include <iostream>
#include <cstdio>
#include <algorithm>
#include <vector>
#include <set>
#include <unordered_map>
#include <unordered_set>
using namespace std;
const int N = 1 << 18;

int n, m, q, a[N];
vector<int> g[N];
set<int> pos[N], lca_pos[N];

int d[N];
vector<int> anc[N];
void dfs(int u, int p) {
	for(int v: g[u]) if(v != p) {
		d[v] = d[u] + 1;
		anc[v].push_back(u);
		for(int j = 0; 1 << j+1 <= d[v]; j++)
			anc[v].push_back(anc[anc[v][j]][j]);
		dfs(v, u);
	}
}
int lca(int u, int v) {
	if(d[v] > d[u]) swap(u, v);
	if(d[u] > d[v]) {
		for(int j = 0; 1 << j <= d[u] - d[v]; j++)
			if(d[u] - d[v] >> j & 1) u = anc[u][j];
	}
	if(u == v) return u;
	for(int j = 18; j >= 0; j--)
		if(j < anc[u].size() && anc[u][j] != anc[v][j])
			u = anc[u][j], v = anc[v][j];
	return anc[u][0];
}

int main() {
	scanf("%d %d %d", &n, &m, &q);
	for(int i = 1, u, v; i < n; i++) {
		scanf("%d %d", &u, &v);
		g[u].push_back(v);
		g[v].push_back(u);
	}
	dfs(1, 0);
	for(int i = 1; i <= m; i++) {
		scanf("%d", a+i);
		pos[a[i]].insert(i);
		if(i > 1) lca_pos[lca(a[i-1], a[i])].insert(i-1);
	}
	for(int z = 0, tp, l, r, v, i; z < q; z++) {
		scanf("%d", &tp);
		if(tp == 1) {
			scanf("%d %d", &i, &v);
			if(i < m) lca_pos[lca(a[i], a[i+1])].erase(i);
			if(i > 1) lca_pos[lca(a[i-1], a[i])].erase(i-1);
			pos[a[i]].erase(i);
			a[i] = v;
			if(i < m) lca_pos[lca(a[i], a[i+1])].insert(i);
			if(i > 1) lca_pos[lca(a[i-1], a[i])].insert(i-1);
			pos[a[i]].insert(i);
		} else {
			scanf("%d %d %d", &l, &r, &v);
			auto it = lca_pos[v].lower_bound(l);
			if(it != lca_pos[v].end() && *it < r) printf("%d %d\n", *it, *it+1);
			else {
				auto it = pos[v].lower_bound(l);
				if(it == pos[v].end() || *it > r) printf("-1 -1\n");
				else printf("%d %d\n", *it, *it);
			}
		}
	}
}

Compilation message (stderr)

treearray.cpp: In function 'void dfs(int, int)':
treearray.cpp:21:24: warning: suggest parentheses around '+' inside '<<' [-Wparentheses]
   for(int j = 0; 1 << j+1 <= d[v]; j++)
                        ^
treearray.cpp: In function 'int lca(int, int)':
treearray.cpp:30:12: warning: suggest parentheses around '-' inside '>>' [-Wparentheses]
    if(d[u] - d[v] >> j & 1) u = anc[u][j];
            ^
treearray.cpp:34:8: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
   if(j < anc[u].size() && anc[u][j] != anc[v][j])
        ^
treearray.cpp: In function 'int main()':
treearray.cpp:40:31: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
  scanf("%d %d %d", &n, &m, &q);
                               ^
treearray.cpp:42:25: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
   scanf("%d %d", &u, &v);
                         ^
treearray.cpp:48:19: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
   scanf("%d", a+i);
                   ^
treearray.cpp:53:19: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
   scanf("%d", &tp);
                   ^
treearray.cpp:55:26: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
    scanf("%d %d", &i, &v);
                          ^
treearray.cpp:64:33: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
    scanf("%d %d %d", &l, &r, &v);
                                 ^

• Subtask 1: 12 / 12
• Subtask 2: 18 / 18
• Subtask 3: 26 / 26
• Subtask 4: 44 / 44