Submission #650265

#	Time	Username	Problem	Language	Result	Execution time	Memory
650265		kingfran1907	Traffic (CEOI11_tra)	C++14	100 / 100	1025 ms	117176 KiB

tra

#include <bits/stdc++.h>
#define X first
#define Y second

using namespace std;
typedef long long llint;

const int maxn = 1e6+10;
const int base = 31337;
const int mod = 1e9+7;
const int inf = 0x3f3f3f3f;
const int logo = 20;
const int off = 1 << logo;
const int treesiz = off << 1;

int n, m, A, B;
int x[maxn], y[maxn];
vector< int > graph[maxn], graph2[maxn];
vector< int > v;
int col[maxn];
pair<int, int> dp[maxn];
vector< pair<int, int> > edg;
bool bio[maxn];

void add(int a, int b) {
	graph[a].push_back(b);
	graph2[b].push_back(a);
	edg.push_back({a, b});
}

void dfs(int x) {
	col[x] = 1;
	for (int tren : graph[x]) {
		if (col[tren] == 0) dfs(tren);
	}
	v.push_back(x);
}

void dfs2(int x, int c) {
	col[x] = c;
	for (int tren : graph2[x]) 
		if (col[tren] == -1) dfs2(tren, c);
}

void dfs3(int x) {
	bio[x] = true;
	for (int tren : graph[x]) 
		if (!bio[tren]) dfs3(tren);
}

bool cmp(int a, int b) {
	return y[a] < y[b];
}

pair<int, int> merg(pair<int, int> a, pair<int, int> b) {
	if (a.X == -1) return b;
	if (b.X == -1) return a;
	return {min(a.X, b.X), max(a.Y, b.Y)};
}

int main() {
	scanf("%d%d%d%d", &n, &m, &A, &B);
	for (int i = 1; i <= n; i++)
		scanf("%d%d", x+i, y+i);
	for (int i = 0; i < m; i++) {
		int a, b, k;
		scanf("%d%d%d", &a, &b, &k);
		add(a, b);
		if (k == 2) add(b, a);
	}

	for (int i = 1; i <= n; i++) 
		if (!col[i]) dfs(i);
	reverse(v.begin(), v.end());
	memset(col, -1, sizeof col);

	vector< int > t;
	for (int tren : v) {
		if (col[tren] == -1) {
			dfs2(tren, tren);
			t.push_back(tren);
		}
	}
	//for (int i = 1; i <= n; i++) printf("%d ", col[i]); printf("\n");

	for (int i = 1; i <= n; i++) graph[i].clear();
	for (auto iter : edg) {
		int x = iter.X;
		int y = iter.Y;
		if (col[x] != col[y]) 
			graph[col[x]].push_back(col[y]);
	}

	memset(bio, false, sizeof bio);
	for (int i = 1; i <= n; i++)
		if (x[i] == 0 && !bio[col[i]]) dfs3(col[i]);

	vector< int > ed;
	for (int i = 1; i <= n; i++) {
		if (x[i] == A && bio[col[i]]) {
			ed.push_back(i);
		}
	}
	for (int i = 1; i <= n; i++) dp[i] = {-1, -1};
	sort(ed.begin(), ed.end(), cmp);
	for (int i = 0; i < ed.size(); i++) {
		int tr = col[ed[i]];
		dp[tr] = merg(dp[tr], {i, i});
	}

	reverse(t.begin(), t.end());
	for (int tren : t) {
		for (int ac : graph[tren]) 
			dp[tren] = merg(dp[tren], dp[ac]);
	}

	ed.clear();
	for (int i = 1; i <= n; i++) {
		if (x[i] == 0) ed.push_back(i);
	}
	sort(ed.begin(), ed.end(), cmp);
	reverse(ed.begin(), ed.end());
	for (int tren : ed) {
		pair<int, int> out = dp[col[tren]];
		if (out.X == -1) printf("0\n");
		else printf("%d\n", out.Y - out.X + 1);
	}
	return 0;
}

Compilation message (stderr)

tra.cpp: In function 'int main()':
tra.cpp:106:20: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
  106 |  for (int i = 0; i < ed.size(); i++) {
      |                  ~~^~~~~~~~~~~
tra.cpp:62:7: warning: ignoring return value of 'int scanf(const char*, ...)' declared with attribute 'warn_unused_result' [-Wunused-result]
   62 |  scanf("%d%d%d%d", &n, &m, &A, &B);
      |  ~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~~~~
tra.cpp:64:8: warning: ignoring return value of 'int scanf(const char*, ...)' declared with attribute 'warn_unused_result' [-Wunused-result]
   64 |   scanf("%d%d", x+i, y+i);
      |   ~~~~~^~~~~~~~~~~~~~~~~~
tra.cpp:67:8: warning: ignoring return value of 'int scanf(const char*, ...)' declared with attribute 'warn_unused_result' [-Wunused-result]
   67 |   scanf("%d%d%d", &a, &b, &k);
      |   ~~~~~^~~~~~~~~~~~~~~~~~~~~~

• Subtask 1: 8 / 8
• Subtask 2: 8 / 8
• Subtask 3: 8 / 8
• Subtask 4: 8 / 8
• Subtask 5: 8 / 8
• Subtask 6: 8 / 8
• Subtask 7: 8 / 8
• Subtask 8: 8 / 8
• Subtask 9: 9 / 9
• Subtask 10: 9 / 9
• Subtask 11: 9 / 9
• Subtask 12: 9 / 9