Submission #447780

#	Time	Username	Problem	Language	Result	Execution time	Memory
447780		rainboy	Sails (IOI07_sails)	C11	100 / 100	194 ms	6416 KiB

sails

#include <stdio.h>

#define N	100000
#define H_	17	/* H_ = ceil(log2(100000)) */
#define N_	(1 << H_)

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

unsigned int X = 12345;

int rand_() {
	return (X *= 3) >> 1;
}

int hh[N], kk[N];

void sort(int *ii, int l, int r) {
	while (l < r) {
		int i = l, j = l, k = r, i_ = ii[l + rand_() % (r - l)], tmp;

		while (j < k)
			if (hh[ii[j]] == hh[i_])
				j++;
			else if (hh[ii[j]] < hh[i_]) {
				tmp = ii[i], ii[i] = ii[j], ii[j] = tmp;
				i++, j++;
			} else {
				k--;
				tmp = ii[j], ii[j] = ii[k], ii[k] = tmp;
			}
		sort(ii, l, i);
		l = k;
	}
}

long long st[N_ * 2]; int lz[N_ * 2], mn[N_ * 2], sz[N_ * 2];

void build() {
	int i;

	for (i = 0; i < N_; i++)
		sz[N_ + i] = 1;
	for (i = N_ - 1; i > 0; i--)
		sz[i] = sz[i << 1 | 0] + sz[i << 1 | 1];
}

void put(int i, int x) {
	st[i] += (long long) sz[i] * x, mn[i] += x;
	if (i < N_)
		lz[i] += x;
}

void pus(int i) {
	if (lz[i])
		put(i << 1 | 0, lz[i]), put(i << 1 | 1, lz[i]), lz[i] = 0;
}

void pul(int i) {
	if (!lz[i]) {
		int l = i << 1, r = l | 1;

		st[i] = st[l] + st[r], mn[i] = mn[l];
	}
}

void push(int i) {
	int h;

	for (h = H_; h > 0; h--)
		pus(i >> h);
}

void pull(int i) {
	while (i > 1)
		pul(i >>= 1);
}

long long query(int l, int r) {
	long long x;

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

void update(int l, int r) {
	int l_ = l += N_, r_ = r += N_;

	if (l > r)
		return;
	push(l_), push(r_);
	for ( ; l <= r; l >>= 1, r >>= 1) {
		if ((l & 1) == 1)
			put(l++, 1);
		if ((r & 1) == 0)
			put(r--, 1);
	}
	pull(l_), pull(r_);
}

int last(int a) {
	int i;

	if (mn[1] > a)
		return -1;
	i = 1;
	while (i < N_) {
		pus(i);
		i = mn[i << 1 | 1] <= a ? i << 1 | 1 : i << 1 | 0;
	}
	return i - N_;
}

int main() {
	static int ii[N];
	int n, i;
	long long ans;

	scanf("%d", &n);
	for (i = 0; i < n; i++) {
		scanf("%d%d", &hh[i], &kk[i]);
		ii[i] = i;
	}
	sort(ii, 0, n);
	build();
	ans = 0;
	for (i = 0; i < n; i++) {
		int i_ = ii[i], l = N_ - hh[i_], r = N_ - hh[i_] + kk[i_] - 1, a, r1, r2;

		ans += query(l, r);
		a = query(r, r), r1 = max(last(a - 1), l - 1), r2 = last(a);
		update(l, r1), update(r2 - (kk[i_] - (r1 - l + 1)) + 1, r2);
	}
	printf("%lld\n", ans);
	return 0;
}

Compilation message (stderr)

sails.c: In function 'main':
sails.c:125:2: warning: ignoring return value of 'scanf' declared with attribute 'warn_unused_result' [-Wunused-result]
  125 |  scanf("%d", &n);
      |  ^~~~~~~~~~~~~~~
sails.c:127:3: warning: ignoring return value of 'scanf' declared with attribute 'warn_unused_result' [-Wunused-result]
  127 |   scanf("%d%d", &hh[i], &kk[i]);
      |   ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~

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