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QOJ
ID | 题目 | 提交者 | 结果 | 用时 | 内存 | 语言 | 文件大小 | 提交时间 | 测评时间 |
---|---|---|---|---|---|---|---|---|---|
#498594 | #7674. Skiing | Max_s_xaM | WA | 1ms | 5756kb | C++14 | 5.7kb | 2024-07-30 16:29:14 | 2024-07-30 16:29:14 |
Judging History
answer
#include <iostream>
#include <algorithm>
#include <cmath>
typedef long long ll;
typedef double lf;
// #define DEBUG 1
struct IO
{
#define MAXSIZE (1 << 20)
#define isdigit(x) (x >= '0' && x <= '9')
char buf[MAXSIZE], *p1, *p2;
char pbuf[MAXSIZE], *pp;
#if DEBUG
#else
IO() : p1(buf), p2(buf), pp(pbuf) {}
~IO() {fwrite(pbuf, 1, pp - pbuf, stdout);}
#endif
#define gc() (p1 == p2 && (p2 = (p1 = buf) + fread(buf, 1, MAXSIZE, stdin), p1 == p2) ? ' ' : *p1++)
#define blank(x) (x == ' ' || x == '\n' || x == '\r' || x == '\t')
template <typename T>
void Read(T &x)
{
#if DEBUG
std::cin >> x;
#else
bool sign = 0; char ch = gc(); x = 0;
for (; !isdigit(ch); ch = gc())
if (ch == '-') sign = 1;
for (; isdigit(ch); ch = gc()) x = x * 10 + (ch ^ 48);
if (sign) x = -x;
#endif
}
void Read(char *s)
{
#if DEBUG
std::cin >> s;
#else
char ch = gc();
for (; blank(ch); ch = gc());
for (; !blank(ch); ch = gc()) *s++ = ch;
*s = 0;
#endif
}
void Read(char &c) {for (c = gc(); blank(c); c = gc());}
void Push(const char &c)
{
#if DEBUG
putchar(c);
#else
if (pp - pbuf == MAXSIZE) fwrite(pbuf, 1, MAXSIZE, stdout), pp = pbuf;
*pp++ = c;
#endif
}
template <typename T>
void Write(T x)
{
if (x < 0) x = -x, Push('-');
static T sta[35];
int top = 0;
do sta[top++] = x % 10, x /= 10; while (x);
while (top) Push(sta[--top] ^ 48);
}
template <typename T>
void Write(T x, char lst) {Write(x), Push(lst);}
} IO;
#define Read(x) IO.Read(x)
#define Write(x, y) IO.Write(x, y)
#define Put(x) IO.Push(x)
using namespace std;
const int MAXN = 260;
const lf eps = 1e-9;
int n; lf vy, ax;
struct Point
{
lf x, y; int id;
bool operator < (const Point &u) const { return (fabs(y - u.y) < eps ? id < u.id : y < u.y); }
}a[MAXN];
lf fmn[MAXN][MAXN], fmx[MAXN][MAXN];
int g[MAXN][MAXN];
int st[MAXN], top;
inline lf Calc1(lf v1, lf v2, lf t)
{
lf h = (ax * t + v1 + v2) / 2;
lf x1 = (ax * t + v2 - v1) / ax / 2, x2 = t - x1;
return ((h + v1) * x1 + (h + v2) * x2) / 2;
}
inline lf Calc2(lf v1, lf v2, lf t)
{
lf h = (-ax * t + v1 + v2) / 2;
lf x1 = (ax * t + v1 - v2) / ax / 2, x2 = t - x1;
return ((h + v1) * x1 + (h + v2) * x2) / 2;
}
int main()
{
// freopen("A.in", "r", stdin);
// freopen("A.out", "w", stdout);
#if DEBUG
#else
ios::sync_with_stdio(0), cin.tie(0);
#endif
Read(n), Read(vy), Read(ax);
for (int i = 1, j = 1; i <= n; i++, j++)
{
Read(a[i].x), Read(a[i].y);
if (a[i].y < 0) { i--, n--; continue; }
a[i].y /= vy, a[i].id = j;
}
a[++n] = Point{0, 0, 0};
sort(a + 1, a + n + 1);
if (ax == 0)
{
bool flag = 0;
for (int i = 1; i <= n; i++)
if (a[i].x == 0) { cout << a[i].id << ' '; flag = 1; }
if (!flag) cout << "Cannot visit any targets\n";
return 0;
}
// for (int i = 1; i <= n; i++) cout << a[i].x << ' ' << a[i].y << '\n';
for (int i = 1; i <= n; i++)
for (int j = 0; j <= n; j++)
fmn[i][j] = 1e18, fmx[i][j] = -1e18;
fmn[1][0] = fmx[1][0] = 0;
for (int i = 2; i <= n; i++)
{
for (int j = 1; j < i; j++)
{
for (int k = 1; k < i; k++)
{
if (fmn[k][j - 1] == 1e18 || fmx[k][j - 1] == -1e18) continue;
lf len = a[i].y - a[k].y, dist = a[i].x - a[k].x;
// cout << i << ' ' << j << ' ' << k << ' ' << len << ' ' << dist << ' ' << len * ax << "\n";
// cout << fmx[k][j - 1] << '\n';
// cout << Calc1(fmx[k][j - 1], fmx[k][j - 1] + len * ax, len) << ' ' << Calc2(fmn[k][j - 1], fmn[k][j - 1] - len * ax, len) << '\n';
if (Calc1(fmx[k][j - 1], fmx[k][j - 1] + len * ax, len) < dist) continue;
if (Calc2(fmn[k][j - 1], fmn[k][j - 1] - len * ax, len) > dist) continue;
lf l = fmn[k][j - 1] - len * ax, r = fmx[k][j - 1] + len * ax, mid, L, R;
while (r - l > eps)
{
mid = (l + r) / 2;
if (Calc1(fmx[k][j - 1], mid, len) < dist) l = mid;
else r = mid;
}
L = l;
l = fmn[k][j - 1] - len * ax, r = fmx[k][j - 1] + len * ax;
while (r - l > eps)
{
mid = (l + r) / 2;
if (Calc2(fmn[k][j - 1], mid, len) > dist) r = mid;
else l = mid;
}
R = l;
if (R < L) continue;
// cout << "Trans " << k << ' ' << j - 1 << " to " << i << ' ' << j << " : " << fmn[k][j - 1] << ' ' << fmx[k][j - 1] << ' ' << L << ' ' << R;
if (fmx[i][j] < R) g[i][j] = k;
// cout << " with " << g[i][j] << '\n';
fmx[i][j] = max(fmx[i][j], R), fmn[i][j] = min(fmn[i][j], L);
}
}
}
int x = 1, y = 0;
for (int i = 1; i <= n; i++)
for (int j = 1; j < i; j++)
if (fmn[i][j] != 1e18 && fmx[i][j] != -1e18 && y < j)
x = i, y = j;
if (y == 0) return cout << "Cannot visit any targets\n", 0;
// cout << "-----------\n";
// cout << x << ' ' << y << "\n";
while (x != 1)
{
st[++top] = a[x].id;
x = g[x][y], y--;
}
for (int i = top; i >= 1; i--) cout << st[i] << ' '; cout << '\n';
return 0;
}
详细
Test #1:
score: 100
Accepted
time: 0ms
memory: 3700kb
input:
4 100 400 -100 100 50 200 -100 300 150 300
output:
1 2 4
result:
ok single line: '1 2 4 '
Test #2:
score: 0
Accepted
time: 1ms
memory: 5620kb
input:
1 100 100 1000 10
output:
Cannot visit any targets
result:
ok single line: 'Cannot visit any targets'
Test #3:
score: 0
Accepted
time: 1ms
memory: 5692kb
input:
0 100 100
output:
Cannot visit any targets
result:
ok single line: 'Cannot visit any targets'
Test #4:
score: 0
Accepted
time: 0ms
memory: 5716kb
input:
2 100 100 100 100 -100 100
output:
Cannot visit any targets
result:
ok single line: 'Cannot visit any targets'
Test #5:
score: 0
Accepted
time: 1ms
memory: 5700kb
input:
2 1000 2001 1000 1000 -1000 1000
output:
1
result:
ok single line: '1 '
Test #6:
score: 0
Accepted
time: 0ms
memory: 3628kb
input:
3 10 30 10 10 -10 10 0 20
output:
1
result:
ok single line: '1 '
Test #7:
score: -100
Wrong Answer
time: 1ms
memory: 5756kb
input:
3 10 31 10 10 -10 10 0 20
output:
2 3
result:
wrong answer 1st lines differ - expected: '1 3', found: '2 3 '