Submission #404276

#	Time	Username	Problem	Language	Result	Execution time	Memory
404276		pure_mem	Regions (IOI09_regions)	C++14	70 / 100	8108 ms	112692 KiB

regions

#include <bits/stdc++.h> 
 
#define X first
#define Y second
#define MP make_pair
#define ll long long
 
using namespace std;
 
const int N = 2e5 + 12, BS = 400;
const ll INF = 1e18;

int n, m, q, timer, rv[N], cl[N];
ll ans1[N / BS + 1][N], ans2[N / BS + 1][N];
vector< int > g[N];
vector< pair<int, int> > his[N];

void dfs(int v){
	his[cl[v]].push_back(MP(++timer, 1));
	for(int to: g[v]){
		dfs(to);
	}
	his[cl[v]].push_back(MP(++timer, -1));		
}

ll calc(int x, int y){
	int i = 0, j = 0, tmp = 0;
	ll r = 0;
	while(i < his[x].size() && j < his[y].size()){
		if(i < his[x].size() && (j == his[y].size() || his[x][i].X < his[y][j].X))
			tmp += his[x][i++].Y;
		else{
			r += (his[y][j++].Y == 1 ? tmp: 0);
		}	
	}
	return r;
}

int main () {
	ios::sync_with_stdio(0), cin.tie(0), cout.tie(0);
	cin >> n >> m >> q >> cl[1];
	for(int i = 2, x;i <= n;i++){
		cin >> x >> cl[i];	
		g[x].push_back(i);
	}
	dfs(1);
	for(int i = 1, z = 0;i <= m;i++){
		if(his[i].size() >= BS){
			rv[i] = ++z;
			for(int j = 1;j <= m;j++)
				ans1[z][j] = calc(i, j), ans2[z][j] = calc(j, i);		
		}
	}
	for(int i = 1, x, y;i <= q;i++){
		cin >> x >> y;
		if(rv[x])
			cout << ans1[rv[x]][y] << endl;
		else if(rv[y])
			cout << ans2[rv[y]][x] << endl;
		else
			cout << calc(x, y) << endl;		
	}
}                

Compilation message (stderr)

regions.cpp: In function 'long long int calc(int, int)':
regions.cpp:29:10: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<std::pair<int, int> >::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   29 |  while(i < his[x].size() && j < his[y].size()){
      |        ~~^~~~~~~~~~~~~~~
regions.cpp:29:31: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<std::pair<int, int> >::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   29 |  while(i < his[x].size() && j < his[y].size()){
      |                             ~~^~~~~~~~~~~~~~~
regions.cpp:30:8: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<std::pair<int, int> >::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   30 |   if(i < his[x].size() && (j == his[y].size() || his[x][i].X < his[y][j].X))
      |      ~~^~~~~~~~~~~~~~~
regions.cpp:30:30: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<std::pair<int, int> >::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   30 |   if(i < his[x].size() && (j == his[y].size() || his[x][i].X < his[y][j].X))
      |                            ~~^~~~~~~~~~~~~~~~

• Subtask 1: 15 / 15
• Subtask 2: 55 / 85