| # |
Submission time |
Handle |
Problem |
Language |
Result |
Execution time |
Memory |
| 544767 |
2022-04-02T16:35:21 Z |
rainboy |
Walk (CEOI06_walk) |
C |
|
93 ms |
8704 KB |
/* upsolve after reading analysis */
#include <stdio.h>
#include <string.h>
#define N 100000
#define N_ (1 << 18)
int abs_(int x) { return x > 0 ? x : -x; }
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 st[N_ * 2], xx[N], n_;
void update(int l, int r, int i) {
for (l += n_, r += n_; l <= r; l >>= 1, r >>= 1) {
if ((l & 1) == 1)
st[l++] = i;
if ((r & 1) == 0)
st[r--] = i;
}
}
int query(int i) {
int i_ = -1;
for (i += n_; i > 0; i >>= 1)
if (i_ == -1 || st[i] != -1 && xx[i_] < xx[st[i]])
i_ = st[i];
return i_;
}
int main() {
static int ii[N * 2], yy[N * 2], yy_[N * 2], dp[N * 2], pp[N * 2], qu[N * 2];
int n, x, y, y_, h, i, j, j0, j1, ans, cnt, cnt_, x1, y1;
scanf("%d%d%d", &x, &y, &n);
for (i = 0; i < n; i++) {
int x1, y1, x2, y2, tmp;
scanf("%d%d%d%d", &x1, &y1, &x2, &y2);
if (x1 > x2)
tmp = x1, x1 = x2, x2 = tmp;
if (y1 > y2)
tmp = y1, y1 = y2, y2 = tmp;
y2++;
xx[i] = x2, yy[i << 1 | 0] = y1, yy[i << 1 | 1] = y2;
}
for (i = 0; i < n * 2; i++)
ii[i] = i;
zz = yy, sort(ii, 0, n * 2);
for (h = 0, y_ = 0; h < n * 2; h++)
yy_[ii[h]] = h + 1 == n * 2 || yy[ii[h + 1]] != yy[ii[h]] ? y_++ : y_;
for (h = -1; h < n * 2; h++)
if (h + 1 == n * 2 || yy[ii[h + 1]] > y) {
y_ = h == -1 ? -1 : yy_[ii[h]];
break;
}
n_ = 1;
while (n_ < n * 2)
n_ <<= 1;
memset(st, -1, n_ * 2 * sizeof *st);
for (i = 0; i < n; i++)
ii[i] = i;
zz = xx, sort(ii, 0, n);
for (h = 0; h < n && xx[ii[h]] < x; h++) {
int i0, i1;
i = ii[h], i0 = i << 1 | 0, i1 = i << 1 | 1;
j = yy_[i0] == 0 ? -1 : query(yy_[i0] - 1), j0 = j << 1 | 0, j1 = j << 1 | 1;
if (j == -1)
dp[i0] = abs_(yy[i0] - 1), pp[i0] = -1;
else if (dp[j0] + yy[i0] - yy[j0] < dp[j1] + yy[j1] - yy[i0] + 1)
dp[i0] = dp[j0] + yy[i0] - yy[j0], pp[i0] = j0;
else
dp[i0] = dp[j1] + yy[j1] - yy[i0] + 1, pp[i0] = j1;
j = query(yy_[i1]), j0 = j << 1 | 0, j1 = j << 1 | 1;
if (j == -1)
dp[i1] = abs_(yy[i1]), pp[i1] = -1;
else if (dp[j0] + yy[i1] - yy[j0] + 1 < dp[j1] + yy[j1] - yy[i1])
dp[i1] = dp[j0] + yy[i1] - yy[j0] + 1, pp[i1] = j0;
else
dp[i1] = dp[j1] + yy[j1] - yy[i1], pp[i1] = j1;
update(yy_[i0], yy_[i1] - 1, i);
}
j = y_ == -1 ? -1 : query(y_), j0 = j << 1 | 0, j1 = j << 1 | 1;
if (j == -1)
ans = abs_(y), i = -1;
else if (dp[j0] + y - yy[j0] + 1 < dp[j1] + yy[j1] - y)
ans = dp[j0] + y - yy[j0] + 1, i = j0;
else
ans = dp[j1] + yy[j1] - y, i = j1;
ans += x;
printf("%d\n", ans);
cnt = 0;
while (i != -1) {
qu[cnt++] = i;
i = pp[i];
}
i = cnt == 0 ? -1 : qu[cnt - 1];
cnt_ = (cnt + 1) * 2;
if ((cnt ? ((i & 1) == 0 ? yy[i] - 1 : yy[i]) : y) == 0)
cnt_--;
if (cnt && xx[qu[0] >> 1] + 1 == x)
cnt_--;
printf("%d\n", cnt_);
x1 = 0, y1 = 0;
while (cnt--) {
int x_, y_;
i = qu[cnt], x_ = xx[i >> 1] + 1, y_ = (i & 1) == 0 ? yy[i] - 1 : yy[i];
if (y1 != y_)
printf("0 %d\n", y_ - y1), y1 = y_;
if (x1 != x_)
printf("%d 0\n", x_ - x1), x1 = x_;
}
if (y1 != y)
printf("0 %d\n", y - y1), y1 = y;
if (x1 != x)
printf("%d 0\n", x - x1), x1 = x;
return 0;
}
Compilation message
walk.c: In function 'query':
walk.c:52:31: warning: suggest parentheses around '&&' within '||' [-Wparentheses]
52 | if (i_ == -1 || st[i] != -1 && xx[i_] < xx[st[i]])
| ~~~~~~~~~~~~^~~~~~~~~~~~~~~~~~~~~
walk.c: In function 'main':
walk.c:61:2: warning: ignoring return value of 'scanf' declared with attribute 'warn_unused_result' [-Wunused-result]
61 | scanf("%d%d%d", &x, &y, &n);
| ^~~~~~~~~~~~~~~~~~~~~~~~~~~
walk.c:65:3: warning: ignoring return value of 'scanf' declared with attribute 'warn_unused_result' [-Wunused-result]
65 | scanf("%d%d%d%d", &x1, &y1, &x2, &y2);
| ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
| # |
Verdict |
Execution time |
Memory |
Grader output |
| 1 |
Correct |
1 ms |
212 KB |
Output is correct |
| 2 |
Correct |
0 ms |
340 KB |
Output is correct |
| 3 |
Correct |
1 ms |
340 KB |
Output is correct |
| 4 |
Correct |
1 ms |
340 KB |
Output is correct |
| 5 |
Correct |
89 ms |
8260 KB |
Output is correct |
| 6 |
Correct |
33 ms |
2728 KB |
Output is correct |
| 7 |
Correct |
45 ms |
4624 KB |
Output is correct |
| 8 |
Correct |
80 ms |
8524 KB |
Output is correct |
| 9 |
Correct |
93 ms |
8620 KB |
Output is correct |
| 10 |
Correct |
84 ms |
8704 KB |
Output is correct |
