Submission #545885

#	Time	Username	Problem	Language	Result	Execution time	Memory
545885		rainboy	Cake (CEOI14_cake)	C11	100 / 100	234 ms	25016 KiB

cake

#include <stdio.h>

#define N	250000
#define Q	500000
#define N_	(1 << 18)	/* N_ = pow2(ceil(log2(N))) */
#define K	10
#define INF	0x3f3f3f3f

int max(int a, int b) { return a > b ? a : b; }

int st[N_ * 2], n_;

void pul(int i) {
	st[i] = max(st[i << 1], st[i << 1 | 1]);
}

void build(int *aa, int n) {
	int i;

	n_ = 1;
	while (n_ < n)
		n_ <<= 1;
	for (i = 0; i < n_; i++)
		st[n_ + i] = i < n ? aa[i] : INF;
	for (i = n_ - 1; i > 0; i--)
		pul(i);
}

void update(int i, int a) {
	st[i += n_] = a;
	while (i > 1)
		pul(i >>= 1);
}

int query(int l, int r) {
	int x = 0;

	for (l += n_, r += n_; l <= r; l >>= 1, r >>= 1) {
		if ((l & 1) == 1)
			x = max(x, st[l++]);
		if ((r & 1) == 0)
			x = max(x, st[r--]);
	}
	return x;
}

int queryr(int l, int a) {
	int r = n_ - 1;

	for (l += n_, r += n_; l <= r; l >>= 1, r >>= 1)
		if ((l & 1) == 1) {
			if (st[l] > a) {
				while (l < n_)
					l = st[l << 1 | 0] > a ? l << 1 | 0 : l << 1 | 1;
				return l -= n_;
			}
			l++;
		}
	return n_;
}

int queryl(int r, int a) {
	int l = 0;

	for (l += n_, r += n_; l <= r; l >>= 1, r >>= 1)
		if ((r & 1) == 0) {
			if (st[r] > a) {
				while (r < n_)
					r = st[r << 1 | 1] > a ? r << 1 | 1 : r << 1 | 0;
				return r -= n_;
			}
			r--;
		}
	return -1;
}

int main() {
	static int idx[N], hh[K], aa[N + Q], tt[N + Q], ii[N + Q], prev[N + Q], next[N + Q];
	int n, q, g, g_, h, i, i_, a;

	scanf("%d%d", &n, &i_), i_--;
	for (i = 0; i < n; i++) {
		scanf("%d", &a), a--;
		idx[a] = i;
	}
	for (a = 0; a < n; a++)
		prev[idx[a]] = a == 0 ? -1 : idx[a - 1], next[idx[a]] = a + 1 == n ? -1 : idx[a + 1];
	for (g = 0; g < K; g++)
		hh[g] = n - 1 - g >= 0 ? idx[n - 1 - g] : -1;
	scanf("%d", &q);
	for (i = 0; i < n; i++)
		ii[i] = i;
	for (h = 0; h < q; h++) {
		static char s[2];

		scanf("%s%d", s, &ii[n + h]), ii[n + h]--;
		tt[h] = s[0] == 'F';
		if (s[0] == 'E') {
			scanf("%d", &g), g--;
			prev[n + h] = hh[g], next[n + h] = next[hh[g]], next[hh[g]] = n + h;
			g_ = g;
			while (g_ < K - 1 && ii[hh[g_]] != ii[n + h])
				g_++;
			while (g_ > g)
				hh[g_] = hh[g_ - 1], g_--;
			hh[g] = n + h;
		}
	}
	for (i = 0; i < n + q; i++)
		if (prev[i] == -1) {
			a = 0;
			while (i != -1)
				aa[i] = a++, i = next[i];
			break;
		}
	build(aa, n);
	for (h = 0; h < q; h++)
		if (tt[h] == 0) {
			update(ii[n + h], aa[n + h]);
		} else {
			i = ii[n + h];
			if (i == i_)
				printf("0\n");
			else if (i < i_)
				printf("%d\n", queryr(i_ + 1, query(i, i_ - 1)) - i - 1);
			else
				printf("%d\n", i - queryl(i_ - 1, query(i_ + 1, i)) - 1);
		}
	return 0;
}

Compilation message (stderr)

cake.c: In function 'main':
cake.c:81:2: warning: ignoring return value of 'scanf' declared with attribute 'warn_unused_result' [-Wunused-result]
   81 |  scanf("%d%d", &n, &i_), i_--;
      |  ^~~~~~~~~~~~~~~~~~~~~~
cake.c:83:3: warning: ignoring return value of 'scanf' declared with attribute 'warn_unused_result' [-Wunused-result]
   83 |   scanf("%d", &a), a--;
      |   ^~~~~~~~~~~~~~~
cake.c:90:2: warning: ignoring return value of 'scanf' declared with attribute 'warn_unused_result' [-Wunused-result]
   90 |  scanf("%d", &q);
      |  ^~~~~~~~~~~~~~~
cake.c:96:3: warning: ignoring return value of 'scanf' declared with attribute 'warn_unused_result' [-Wunused-result]
   96 |   scanf("%s%d", s, &ii[n + h]), ii[n + h]--;
      |   ^~~~~~~~~~~~~~~~~~~~~~~~~~~~
cake.c:99:4: warning: ignoring return value of 'scanf' declared with attribute 'warn_unused_result' [-Wunused-result]
   99 |    scanf("%d", &g), g--;
      |    ^~~~~~~~~~~~~~~

• Subtask 1: 15 / 15
• Subtask 2: 15 / 15
• Subtask 3: 20 / 20
• Subtask 4: 50 / 50