Submission #209507

#TimeUsernameProblemLanguageResultExecution timeMemory
209507mieszko11bBridges (APIO19_bridges)C++14
73 / 100
3100 ms25452 KiB
#include <bits/stdc++.h>

using namespace std;

using ii = pair<int, int>;

#define X first
#define Y second

const int SQRT = 600;

int n, m;
int a[100007], b[100007], c[100007];
int q;
int t[100007], d[100007], e[100007], ans[100007];
bool changed[100007];
int lastw[100007];
int maxv;
vector<int> not_changed[200007];
vector<int> G[50007];

void readint(int &x) {
	x = 0;
	char c;
	do
		c = getchar_unlocked();
	while(c < '0' || c > '9');
	
	do {
		x = x * 10 + c - '0';
		c = getchar_unlocked();
	} while(c >= '0' && c <= '9');
}

int p[50007], ran[50007];
bool vis[50007];

struct DSU {
	int n;
	int cnt;
	vector<int> aff;
	
	DSU(int _n) {
		n = _n;
		for(int i = 1 ; i <= n ; i++) {
			p[i] = i;
			ran[i] = 1;
		}
	}
	
	int Find(int i) {
		if(p[i] == i)
			return i;
		return p[i] = Find(p[i]);
	}
	
	void Union(int a, int b) {
		a = Find(a);
		b = Find(b);
		
		if(a == b)
			return ;
			
		if(ran[a] < ran[b]) {
			p[a] = b;
			ran[b] += ran[a];
		} else {
			p[b] = a;
			ran[a] += ran[b];
		}
	}
	
	void dfs(int w) {
		if(vis[w])
			return ;
		vis[w] = 1;
		aff.push_back(w);
		cnt += ran[w];
		for(int u : G[w])
			dfs(u);
	}
	
	int count(vector<int> &E, int w) {
		for(int e : E) {
			G[Find(a[e])].push_back(Find(b[e]));
			G[Find(b[e])].push_back(Find(a[e]));
		}
		cnt = 0;
		dfs(Find(w));
		for(int x : aff)
			vis[x] = 0;
		aff.clear();
		for(int e : E) {
			G[Find(a[e])].clear();
			G[Find(b[e])].clear();
		}
		return cnt;
	}
};


void process_queries(int x, int y) {
	vector<ii> Q;
	vector<int> chacha;
	chacha.reserve(y - x + 1);
	Q.reserve(y - x + 1);
	memset(changed, 0, sizeof changed);
	for(int i = x ; i <= y ; i++) {
		if(t[i] == 1)
			changed[d[i]] = 1;
		else
			Q.emplace_back(e[i], i);
	}
	for(int j = 0 ; j < maxv ; j++)
		not_changed[j].clear();
	for(int i = 1 ; i <= m ; i++) {
		if(!changed[i])
			not_changed[c[i]].push_back(i);
		else
			chacha.push_back(i);
	}
	sort(Q.begin(), Q.end(), greater<ii>());
	
	DSU *dsu = new DSU(n);
	
	int v = maxv;
	for(int j = 0 ; j < Q.size() ; j++) {
		int q = Q[j].Y;
		
		for(int i = e[q] ; i < v ; i++)
			for(int e : not_changed[i])
				dsu->Union(a[e], b[e]);
		v = e[q];
				
		for(int e : chacha)
			lastw[e] = c[e];
		for(int k = x ; k < q ; k++)
			if(t[k] == 1)
				lastw[d[k]] = e[k];
		vector<int> E;
		E.reserve(y - x + 1);
		for(int e : chacha)
			if(lastw[e] >= ::e[q])
				E.push_back(e);
		ans[q] = dsu->count(E, d[q]);
	}

	for(int k = x ; k <= y ; k++)
		if(t[k] == 1)
			c[d[k]] = e[k];	
			
	delete dsu;
}

int main() {
	//~ scanf("%d%d",&n, &m);
	readint(n);
	readint(m);
	
	vector<int> hlp;
	
	for(int i = 1 ; i <= m ; i++) {
		//~ scanf("%d%d%d", &a[i], &b[i], &c[i]);
		readint(a[i]);
		readint(b[i]);
		readint(c[i]);
		hlp.push_back(c[i]);
	}
	//~ scanf("%d", &q);
	readint(q);
	for(int i = 1 ; i <= q ; i++) {
		//~ scanf("%d%d%d", &t[i], &d[i], &e[i]);
		readint(t[i]);
		readint(d[i]);
		readint(e[i]);
		hlp.push_back(e[i]);
	}
		
	sort(hlp.begin(), hlp.end());
	hlp.resize(distance(hlp.begin(), unique(hlp.begin(), hlp.end())));
	map<int, int> M;
	for(int i = 0 ; i < hlp.size() ; i++)
		M[hlp[i]] = i;
	maxv = hlp.size();
	for(int i = 1 ; i <= m ; i++)
		c[i] = M[c[i]];
	for(int i = 1 ; i <= q ; i++)
		e[i] = M[e[i]];
		
	for(int i = 1 ; i <= q ; i += SQRT)
		process_queries(i, min(i + SQRT - 1, q));
		
	for(int i = 1 ; i <= q ; i++)
		if(ans[i])
			printf("%d\n", ans[i]);
		
	return 0;
}

Compilation message (stderr)

bridges.cpp: In function 'void process_queries(int, int)':
bridges.cpp:127:20: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
  for(int j = 0 ; j < Q.size() ; j++) {
                  ~~^~~~~~~~~~
bridges.cpp: In function 'int main()':
bridges.cpp:182:20: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
  for(int i = 0 ; i < hlp.size() ; i++)
                  ~~^~~~~~~~~~~~
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