Submission #140573

# Submission time Handle Problem Language Result Execution time Memory
140573 2019-08-03T15:04:33 Z luciocf Street Lamps (APIO19_street_lamps) C++17
40 / 100
5000 ms 11000 KB
#include <bits/stdc++.h>

using namespace std;

typedef pair<int, int> pii;

const int maxn = 3e5+10;

struct Op
{
	int type;
	int ind;
} query[maxn];

struct E
{
	int type;
	int l, r;
} event[maxn];

int n, q;

int last[maxn];
int ans[maxn];

int pai[maxn], peso[maxn];
int edge[maxn], nivel[maxn];

bool on[maxn];
bool mark[maxn];

void init(void)
{
	for (int i = 1; i <= n+1; i++)
		pai[i] = i, peso[i] = 1;
}

int Find(int x)
{
	if (pai[x] == x) return x;
	return Find(pai[x]);
}

void Join(int x, int y, int t)
{
	x = Find(x), y = Find(y);
	if (x == y) return;

	if (peso[x] < peso[y]) swap(x, y);

	pai[y] = x, peso[x] += peso[y];
	edge[y] = t;
}

int dfs(int u, int p)
{
	if (u == p) return 0;

	return nivel[u] = dfs(pai[u], p)+1;
}

int lca(int u, int v)
{
	int ans = 0;

	while (u != v)
	{
		if (nivel[u] > nivel[v]) ans = max(ans, edge[u]), u = pai[u];
		else ans = max(ans, edge[v]), v = pai[v];
	}

	return ans;
}

void solve_small(void)
{
	for (int i = 1; i <= q; i++)
	{
		string op;
		cin >> op;

		if (op == "toggle")
		{
			int ind;
			scanf("%d", &ind);

			query[i] = {0, ind};
		}
		else
		{
			int l, r;
			scanf("%d %d", &l, &r);

			query[i] = {1, -1};

			int ans = 0;
			for (int j = 1; j <= n; j++)
				mark[j] = on[j];

			for (int j = 1; j <= i; j++)
			{
				if (query[j].type == 1)
				{
					bool ok = 1;
					for (int k = l; k < r; k++)
						if (!mark[k])
							ok = 0;

					if (ok) ans++;
				}
				else
				{

					bool ok = 1;
					for (int k = l; k < r; k++)
						if (!mark[k])
							ok = 0;

					if (ok) ans++;

					mark[query[j].ind] = !mark[query[j].ind];
				}
			}

			printf("%d\n", ans);
		}
	}
}

void solve_two(void)
{
	for (int i = 1; i <= q; i++)
	{
		if (event[i].type == 0)
		{
			int ind = event[i].l;

			on[ind] = !on[ind];

			if (!on[ind])
				ans[ind] += (i-last[ind]);

			last[ind] = i;
		}
		else
		{
			int l = event[i].l, r = event[i].r;

			int tot = ans[l];

			if (on[l]) tot += (i-last[l]);

			printf("%d\n", tot);
		}
	}
}

int main(void)
{
	scanf("%d %d", &n, &q);

	init();

	for (int i = 1; i <= n; i++)
	{
		char x;
		scanf(" %c", &x);

		if (x == '1')
		{
			on[i] = true;
			Join(i, i+1, 0);
		}
	}

	if (n <= 100 && q <= 100)
	{
		solve_small();
		return 0;
	}

	bool ok = 1;

	for (int i = 1; i <= q; i++)
	{
		string s;
		cin >> s;

		if (s == "toggle")
		{
			int ind;
			scanf("%d", &ind);

			event[i] = {0, ind, -1};

			Join(ind, ind+1, i);
		}
		else
		{
			int l, r;
			scanf("%d %d", &l, &r);

			event[i] = {1, l, r};

			if (r != l+1) ok = 0;
		}
	}

	if (ok)
	{
		solve_two();
		return 0;
	}

	for (int i = 1; i <= n+1; i++)
		dfs(i, Find(i));

	for (int i = 1; i <= q; i++)
	{
		if (event[i].type)
		{
			int l = event[i].l, r = event[i].r;

			int first = lca(l, r);

			if (first > i || Find(l) != Find(r)) printf("0\n");
			else printf("%d\n", i-first);
		}
	}
}

Compilation message

street_lamps.cpp: In function 'void solve_two()':
street_lamps.cpp:147:24: warning: unused variable 'r' [-Wunused-variable]
    int l = event[i].l, r = event[i].r;
                        ^
street_lamps.cpp: In function 'void solve_small()':
street_lamps.cpp:85:9: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
    scanf("%d", &ind);
    ~~~~~^~~~~~~~~~~~
street_lamps.cpp:92:9: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
    scanf("%d %d", &l, &r);
    ~~~~~^~~~~~~~~~~~~~~~~
street_lamps.cpp: In function 'int main()':
street_lamps.cpp:160:7: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
  scanf("%d %d", &n, &q);
  ~~~~~^~~~~~~~~~~~~~~~~
street_lamps.cpp:167:8: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
   scanf(" %c", &x);
   ~~~~~^~~~~~~~~~~
street_lamps.cpp:192:9: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
    scanf("%d", &ind);
    ~~~~~^~~~~~~~~~~~
street_lamps.cpp:201:9: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
    scanf("%d %d", &l, &r);
    ~~~~~^~~~~~~~~~~~~~~~~
# Verdict Execution time Memory Grader output
1 Correct 2 ms 376 KB Output is correct
2 Correct 2 ms 376 KB Output is correct
3 Correct 2 ms 376 KB Output is correct
4 Correct 3 ms 376 KB Output is correct
5 Correct 2 ms 380 KB Output is correct
6 Correct 3 ms 376 KB Output is correct
7 Correct 2 ms 376 KB Output is correct
# Verdict Execution time Memory Grader output
1 Correct 236 ms 4776 KB Output is correct
2 Correct 242 ms 4856 KB Output is correct
3 Correct 252 ms 4856 KB Output is correct
4 Correct 312 ms 10804 KB Output is correct
5 Correct 316 ms 9856 KB Output is correct
6 Correct 297 ms 10792 KB Output is correct
7 Correct 283 ms 6904 KB Output is correct
8 Correct 295 ms 9736 KB Output is correct
# Verdict Execution time Memory Grader output
1 Correct 3 ms 376 KB Output is correct
2 Correct 3 ms 376 KB Output is correct
3 Correct 3 ms 376 KB Output is correct
4 Correct 3 ms 376 KB Output is correct
5 Correct 305 ms 8944 KB Output is correct
6 Correct 325 ms 9180 KB Output is correct
7 Correct 333 ms 9320 KB Output is correct
8 Correct 309 ms 11000 KB Output is correct
9 Correct 193 ms 4216 KB Output is correct
10 Correct 206 ms 4600 KB Output is correct
11 Correct 207 ms 4600 KB Output is correct
12 Execution timed out 5085 ms 6364 KB Time limit exceeded
13 Halted 0 ms 0 KB -
# Verdict Execution time Memory Grader output
1 Execution timed out 5078 ms 376 KB Time limit exceeded
2 Halted 0 ms 0 KB -
# Verdict Execution time Memory Grader output
1 Correct 2 ms 376 KB Output is correct
2 Correct 2 ms 376 KB Output is correct
3 Correct 2 ms 376 KB Output is correct
4 Correct 3 ms 376 KB Output is correct
5 Correct 2 ms 380 KB Output is correct
6 Correct 3 ms 376 KB Output is correct
7 Correct 2 ms 376 KB Output is correct
8 Correct 236 ms 4776 KB Output is correct
9 Correct 242 ms 4856 KB Output is correct
10 Correct 252 ms 4856 KB Output is correct
11 Correct 312 ms 10804 KB Output is correct
12 Correct 316 ms 9856 KB Output is correct
13 Correct 297 ms 10792 KB Output is correct
14 Correct 283 ms 6904 KB Output is correct
15 Correct 295 ms 9736 KB Output is correct
16 Correct 3 ms 376 KB Output is correct
17 Correct 3 ms 376 KB Output is correct
18 Correct 3 ms 376 KB Output is correct
19 Correct 3 ms 376 KB Output is correct
20 Correct 305 ms 8944 KB Output is correct
21 Correct 325 ms 9180 KB Output is correct
22 Correct 333 ms 9320 KB Output is correct
23 Correct 309 ms 11000 KB Output is correct
24 Correct 193 ms 4216 KB Output is correct
25 Correct 206 ms 4600 KB Output is correct
26 Correct 207 ms 4600 KB Output is correct
27 Execution timed out 5085 ms 6364 KB Time limit exceeded
28 Halted 0 ms 0 KB -