oj.uz

Submission #140571

# Submission time Handle Problem Language Result Execution time Memory
140571 2019-08-03T15:00:21 Z luciocf Street Lamps (APIO19_street_lamps) C++14
40 / 100
 5000 ms 11276 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;

	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; 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 'int dfs(int, int)':
street_lamps.cpp:60:1: warning: control reaches end of non-void function [-Wreturn-type]
 }
 ^
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);
    ~~~~~^~~~~~~~~~~~~~~~~

Subtask #1
20.0 / 20.0

# Verdict Execution time Memory Grader output
1 Correct 2 ms 376 KB Output is correct
2 Correct 3 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 376 KB Output is correct
6 Correct 3 ms 376 KB Output is correct
7 Correct 3 ms 376 KB Output is correct

Subtask #2
20.0 / 20.0

# Verdict Execution time Memory Grader output
1 Correct 236 ms 5272 KB Output is correct
2 Correct 241 ms 5496 KB Output is correct
3 Correct 253 ms 5520 KB Output is correct
4 Correct 309 ms 11256 KB Output is correct
5 Correct 323 ms 10504 KB Output is correct
6 Correct 308 ms 11276 KB Output is correct
7 Correct 296 ms 7436 KB Output is correct
8 Correct 298 ms 10280 KB Output is correct

Subtask #3
0 / 20.0

# Verdict Execution time Memory Grader output
1 Correct 3 ms 376 KB Output is correct
2 Incorrect 3 ms 376 KB Output isn't correct
3 Halted 0 ms 0 KB -

Subtask #4
0 / 20.0

# Verdict Execution time Memory Grader output
1 Execution timed out 5061 ms 376 KB Time limit exceeded
2 Halted 0 ms 0 KB -

Subtask #5
0 / 20.0

# Verdict Execution time Memory Grader output
1 Correct 2 ms 376 KB Output is correct
2 Correct 3 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 376 KB Output is correct
6 Correct 3 ms 376 KB Output is correct
7 Correct 3 ms 376 KB Output is correct
8 Correct 236 ms 5272 KB Output is correct
9 Correct 241 ms 5496 KB Output is correct
10 Correct 253 ms 5520 KB Output is correct
11 Correct 309 ms 11256 KB Output is correct
12 Correct 323 ms 10504 KB Output is correct
13 Correct 308 ms 11276 KB Output is correct
14 Correct 296 ms 7436 KB Output is correct
15 Correct 298 ms 10280 KB Output is correct
16 Correct 3 ms 376 KB Output is correct
17 Incorrect 3 ms 376 KB Output isn't correct
18 Halted 0 ms 0 KB -