Submission #365322

#	Time	Username	Problem	Language	Result	Execution time	Memory
365322		GioChkhaidze	철도 요금 (JOI16_ho_t3)	C++14	100 / 100	218 ms	26092 KiB

2016_ho_t3

#include <bits/stdc++.h>
 
#define pb push_back
#define F first
#define S second
 
using namespace std;
 
const int N = 2e5 + 5;
 
int n, m, q, ans;
int in[N], d[N], a[N], b[N];
bool act[N], ed[N], used[N];
vector < pair < int , int > > v[N], g[N];
queue < int > qr;
 
void lazy(int x, int idx) {
	--in[x];
	ed[idx] = true;
	if (!in[x]) {
		++ans;
		for (int i = 0; i < g[x].size(); ++i) {
			int to = g[x][i].F, id = g[x][i].S;
			if (ed[id]) continue;
			lazy(to, id);
		}
	}
}
 
main () {
	ios::sync_with_stdio(false);
	cin.tie(NULL), cout.tie(NULL);
	cin >> n >> m >> q;
	for (int i = 1; i <= m; ++i) {
		cin >> a[i] >> b[i];
		v[a[i]].pb({b[i], i});
		v[b[i]].pb({a[i], i});
	}
	
	for (int i = 2; i <= n; ++i) {
		d[i] = 1e9;
	}
 
	qr.push(1);
	while (!qr.empty()) {
		int x = qr.front();
		qr.pop();
		
		for (int i = 0; i < v[x].size(); ++i) {
			int to = v[x][i].F, id = v[x][i].S;
			if (d[x] + 1 < d[to]) {
				d[to] = d[x] + 1;
				qr.push(to);
			}
			
			if (d[x] + 1 == d[to]) {
				g[x].pb({to, id});	
				act[id] = true;
				++in[to];
			}
		} 
	}
 
	for (int i = 1; i <= m; ++i) {
		if (d[a[i]] > d[b[i]]) swap(a[i], b[i]);
	}
 
	for (int i = 1; i <= q; ++i) {
		int x;
		cin >> x;
		
		if (act[x] && !ed[x]) {
			lazy(b[x], x);
		}
 
		cout << ans << "\n";
	}
}

Compilation message (stderr)

2016_ho_t3.cpp: In function 'void lazy(int, int)':
2016_ho_t3.cpp:22:21: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<std::pair<int, int> >::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   22 |   for (int i = 0; i < g[x].size(); ++i) {
      |                   ~~^~~~~~~~~~~~~
2016_ho_t3.cpp: At global scope:
2016_ho_t3.cpp:30:7: warning: ISO C++ forbids declaration of 'main' with no type [-Wreturn-type]
   30 | main () {
      |       ^
2016_ho_t3.cpp: In function 'int main()':
2016_ho_t3.cpp:49:21: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<std::pair<int, int> >::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   49 |   for (int i = 0; i < v[x].size(); ++i) {
      |                   ~~^~~~~~~~~~~~~

• Subtask 1: 12 / 12
• Subtask 2: 14 / 14
• Subtask 3: 35 / 35
• Subtask 4: 39 / 39