oj.uz

Submission #140575

# Submission time Handle Problem Language Result Execution time Memory
140575 2019-08-03T15:07:22 Z luciocf Street Lamps (APIO19_street_lamps) C++14
60 / 100
 408 ms 16844 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++)
		if (nivel[i] == 0 && i != Find(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;

			if (Find(l) != Find(r))
			{
				printf("0\n");
				continue;
			}

			int first = lca(l, r);

			if (first > i) 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);
    ~~~~~^~~~~~~~~~~~~~~~~

Subtask #1
20.0 / 20.0

# 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 420 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 4864 KB Output is correct
2 Correct 240 ms 5016 KB Output is correct
3 Correct 247 ms 4856 KB Output is correct
4 Correct 312 ms 10744 KB Output is correct
5 Correct 313 ms 9820 KB Output is correct
6 Correct 300 ms 10696 KB Output is correct
7 Correct 281 ms 6760 KB Output is correct
8 Correct 295 ms 9720 KB Output is correct

Subtask #3
20.0 / 20.0

# 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 352 KB Output is correct
4 Correct 3 ms 380 KB Output is correct
5 Correct 310 ms 8844 KB Output is correct
6 Correct 337 ms 9176 KB Output is correct
7 Correct 408 ms 9232 KB Output is correct
8 Correct 320 ms 10872 KB Output is correct
9 Correct 192 ms 4060 KB Output is correct
10 Correct 219 ms 4344 KB Output is correct
11 Correct 207 ms 4472 KB Output is correct
12 Correct 277 ms 6828 KB Output is correct
13 Correct 322 ms 16844 KB Output is correct

Subtask #4
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 #5
0 / 20.0

# 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 420 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 4864 KB Output is correct
9 Correct 240 ms 5016 KB Output is correct
10 Correct 247 ms 4856 KB Output is correct
11 Correct 312 ms 10744 KB Output is correct
12 Correct 313 ms 9820 KB Output is correct
13 Correct 300 ms 10696 KB Output is correct
14 Correct 281 ms 6760 KB Output is correct
15 Correct 295 ms 9720 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 352 KB Output is correct
19 Correct 3 ms 380 KB Output is correct
20 Correct 310 ms 8844 KB Output is correct
21 Correct 337 ms 9176 KB Output is correct
22 Correct 408 ms 9232 KB Output is correct
23 Correct 320 ms 10872 KB Output is correct
24 Correct 192 ms 4060 KB Output is correct
25 Correct 219 ms 4344 KB Output is correct
26 Correct 207 ms 4472 KB Output is correct
27 Correct 277 ms 6828 KB Output is correct
28 Correct 322 ms 16844 KB Output is correct
29 Correct 3 ms 376 KB Output is correct
30 Incorrect 3 ms 376 KB Output isn't correct
31 Halted 0 ms 0 KB -