Submission #471754

#	Time	Username	Problem	Language	Result	Execution time	Memory
471754		rainboy	Krov (COCI17_krov)	C11	112 / 140	1587 ms	80452 KiB

krov

#include <stdio.h>
 
#define N	100000
#define LN	17	/* LN = ceil(log2(N)) */
#define N_	(1 + N * 4 + N * 2 * (LN + 1))
#define INF	0x3f3f3f3f
#define LINF	0x3f3f3f3f3f3f3f3fLL
 
long long min(long long a, long long b) { return a < b ? a : b; }
int max(int a, int b) { return a > b ? a : b; }
 
unsigned int X = 12345;
 
int rand_() {
	return (X *= 3) >> 1;
}
 
int *zz;
 
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 (zz[ii[j]] == zz[i_])
				j++;
			else if (zz[ii[j]] < zz[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;
	}
}
 
int ll[1 + N_], rr[1 + N_], cnt[1 + N_], _; long long sum[1 + N_];
 
int build(int *aa, int l, int r) {
	int t_ = _++;
 
	if (r - l == 1)
		ll[t_] = 0, rr[t_] = 0, cnt[t_] = 1, sum[t_] = aa[l];
	else {
		int m = (l + r) / 2;

		ll[t_] = build(aa, l, m), rr[t_] = build(aa, m, r);
		cnt[t_] = cnt[ll[t_]] + cnt[rr[t_]];
		sum[t_] = sum[ll[t_]] + sum[rr[t_]];
	}
	return t_;
}

int update(int t, int l, int r, int i, int c, int s) {
	int t_ = _++;
 
	if (r - l == 1)
		ll[t_] = 0, rr[t_] = 0, cnt[t_] = c, sum[t_] = s;
	else {
		int m = (l + r) / 2;
 
		if (i < m)
			ll[t_] = update(ll[t], l, m, i, c, s), rr[t_] = rr[t];
		else
			ll[t_] = ll[t], rr[t_] = update(rr[t], m, r, i, c, s);
		cnt[t_] = cnt[ll[t_]] + cnt[rr[t_]];
		sum[t_] = sum[ll[t_]] + sum[rr[t_]];
	}
	return t_;
}
 
int c; long long s;
 
void query(int t, int l, int r, int ql, int qr) {
	int m;
 
	if (qr <= l || r <= ql || t == 0)
		return;
	if (ql <= l && r <= qr) {
		c += cnt[t], s += sum[t];
		return;
	}
	m = (l + r) / 2;
	query(ll[t], l, m, ql, qr), query(rr[t], m, r, ql, qr);
}
 
long long query_(int *aa, int *tt, int n, int l, int r, int a) {
	int lower = -1, upper = n;
 
	while (upper - lower > 1) {
		int i = (lower + upper) / 2;
 
		if (aa[i] <= a)
			lower = i;
		else
			upper = i;
	}
	s = 0, c = 0;
	query(tt[upper], 0, n, l, r);
	return s - (long long) c * a;
}
 
int main() {
	static int xx[N], aa[N], aa_[N], bb[N], bb_[N], ii[N], tta[N + 1], ttb[N + 1];
	int n, i;
	long long ans;
 
	scanf("%d", &n);
	for (i = 0; i < n; i++) {
		scanf("%d", &xx[i]);
		aa[i] = xx[i] - i, bb[i] = xx[i] + i;
	}
	_ = 1;
	for (i = 0; i < n; i++)
		ii[i] = i;
	zz = aa, sort(ii, 0, n);
	tta[0] = build(aa, 0, n);
	for (i = 0; i < n; i++)
		aa_[i] = aa[ii[i]], tta[i + 1] = update(tta[i], 0, n, ii[i], -1, -aa[ii[i]]);
	for (i = 0; i < n; i++)
		ii[i] = i;
	zz = bb, sort(ii, 0, n);
	ttb[0] = build(bb, 0, n);
	for (i = 0; i < n; i++)
		bb_[i] = bb[ii[i]], ttb[i + 1] = update(ttb[i], 0, n, ii[i], -1, -bb[ii[i]]);
	ans = LINF;
	for (i = 0; i < n; i++) {
		int lower = max(i + 1, n - i) - 1, upper = INF;
 
		while (upper - lower > 1) {
			int x = (lower + upper) / 2;
 
			if (query_(aa_, tta, n, 0, i + 1, x - i) + query_(bb_, ttb, n, i + 1, n, x + i) <= query_(aa_, tta, n, 0, i + 1, x + 1 - i) + query_(bb_, ttb, n, i + 1, n, x + 1 + i))
				upper = x;
			else
				lower = x;
		}
		ans = min(ans, query_(aa_, tta, n, 0, i + 1, upper - i) + query_(bb_, ttb, n, i + 1, n, upper + i));
	}
	printf("%lld\n", ans);
	return 0;
}

Compilation message (stderr)

krov.c: In function 'main':
krov.c:110:2: warning: ignoring return value of 'scanf' declared with attribute 'warn_unused_result' [-Wunused-result]
  110 |  scanf("%d", &n);
      |  ^~~~~~~~~~~~~~~
krov.c:112:3: warning: ignoring return value of 'scanf' declared with attribute 'warn_unused_result' [-Wunused-result]
  112 |   scanf("%d", &xx[i]);
      |   ^~~~~~~~~~~~~~~~~~~

• Subtask 1: 14 / 14
• Subtask 2: 14 / 14
• Subtask 3: 14 / 14
• Subtask 4: 14 / 14
• Subtask 5: 14 / 14
• Subtask 6: 14 / 14
• Subtask 7: 14 / 14
• Subtask 8: 14 / 14
• Subtask 9: 0 / 14
• Subtask 10: 0 / 14