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QOJ
ID | Problem | Submitter | Result | Time | Memory | Language | File size | Submit time | Judge time |
---|---|---|---|---|---|---|---|---|---|
#122070 | #6570. Who Watches the Watchmen? | tacoref# | WA | 14ms | 3540kb | C++17 | 5.2kb | 2023-07-09 13:16:09 | 2023-07-09 13:16:12 |
Judging History
answer
#include <bits/stdc++.h>
using namespace std;
using lint = long long;
#define sz(v) ((int)(v).size())
#define all(v) (v).begin(), (v).end()
using P3 = array<lint, 3>;
using pi = array<lint, 2>;
const int MAXN = 1005;
struct mcmf {
struct edg {
int pos, cap, rev;
lint cost;
};
vector<edg> gph[MAXN];
void clear() {
for (int i = 0; i < MAXN; i++)
gph[i].clear();
}
void addEdge(int s, int e, int x, lint c) {
gph[s].push_back({e, x, sz(gph[e]), c});
gph[e].push_back({s, 0, sz(gph[s]) - 1, -c});
}
lint dist[MAXN];
int pa[MAXN], pe[MAXN];
bool inque[MAXN];
bool spfa(int src, int sink) {
memset(dist, 0x3f, sizeof(dist));
memset(inque, 0, sizeof(inque));
queue<int> que;
dist[src] = 0;
inque[src] = 1;
que.push(src);
bool ok = 0;
while (sz(que)) {
int x = que.front();
que.pop();
if (x == sink)
ok = 1;
inque[x] = 0;
for (int i = 0; i < sz(gph[x]); i++) {
edg e = gph[x][i];
if (e.cap > 0 && dist[e.pos] > dist[x] + e.cost) {
dist[e.pos] = dist[x] + e.cost;
pa[e.pos] = x;
pe[e.pos] = i;
if (!inque[e.pos]) {
inque[e.pos] = 1;
que.push(e.pos);
}
}
}
}
return ok;
}
lint match(int src, int sink) {
lint ret = 0;
while (spfa(src, sink)) {
lint cap = 1e18;
for (int pos = sink; pos != src; pos = pa[pos]) {
cap = min(cap, (lint)gph[pa[pos]][pe[pos]].cap);
}
ret += cap * dist[sink];
for (int pos = sink; pos != src; pos = pa[pos]) {
int rev = gph[pa[pos]][pe[pos]].rev;
gph[pa[pos]][pe[pos]].cap -= cap;
gph[pos][rev].cap += cap;
}
}
return ret;
}
} mcmf;
lint hung(vector<vector<int>> a) {
int n = sz(a);
for (int i = 0; i < n; i++) {
mcmf.addEdge(0, i + 1, 1, 0);
mcmf.addEdge(i + n + 1, n + n + 1, 1, 0);
for (int j = 0; j < n; j++) {
mcmf.addEdge(i + 1, j + n + 1, 1, a[i][j]);
}
}
return mcmf.match(0, 2 * n + 1);
}
P3 operator-(P3 a, P3 b) {
for (int i = 0; i < 3; i++)
a[i] -= b[i];
return a;
}
P3 norm(P3 a) {
lint g = 0;
for (int i = 0; i < 3; i++) {
g = gcd(g, abs(a[i]));
}
assert(g > 0);
for (int i = 0; i < 3; i++) {
a[i] /= g;
}
return a;
}
P3 cross(const P3 &a, const P3 &b) { return P3{a[1] * b[2] - a[2] * b[1], a[2] * b[0] - a[0] * b[2], a[0] * b[1] - a[1] * b[0]}; }
P3 cross(const P3 &a, const P3 &b, const P3 &c) { return cross(b - a, c - a); }
bool isMult(const P3 &a, const P3 &b) {
P3 c = cross(a, b);
for (int i = 0; i < sz(c); i++) {
if (c[i] != 0)
return 0;
}
return 1;
}
bool collinear(const P3 &a, const P3 &b, const P3 &c) { return isMult(b - a, c - a); }
lint dist(P3 a, P3 b) {
lint ans = 0;
for (int i = 0; i < 3; i++)
ans += (a[i] - b[i]) * (a[i] - b[i]);
return ans;
}
lint dot(P3 a, P3 b) {
lint ans = 0;
for (int i = 0; i < 3; i++)
ans += a[i] * b[i];
return ans;
}
bool is_collinear(vector<P3> p) {
for (int i = 2; i < sz(p); i++) {
if (!collinear(p[0], p[1], p[i]))
return false;
}
return true;
}
int haveSex(vector<P3> p, vector<P3> d, int n) {
P3 arg = p[1] - p[0];
int dap = 1557;
for (int i = 0; i < 2; i++) {
vector<int> ord(n);
iota(all(ord), 0);
sort(all(ord), [&](const int &x, const int &y) { return dot(p[x], arg) < dot(p[y], arg); });
for (int i = 0; i < n; i++) {
vector<int> remord = ord;
remord.erase(remord.begin() + i);
int isol = ord[i];
int cost = 0;
for (int i = 0; i + 1 < sz(remord); i++) {
P3 z = p[remord[i + 1]] - p[remord[i]];
P3 head = d[remord[i]];
if (norm(z) != norm(head))
cost++;
}
int isolCollinear = isMult(d[isol], arg);
int backCollinear = isMult(d[remord[n - 2]], arg);
if (isolCollinear || backCollinear) {
cost += isolCollinear;
cost += backCollinear;
} else {
P3 a = arg;
P3 b = d[remord[n - 2]];
P3 c = d[isol];
if (isMult(b, c)) {
cost++;
} else {
P3 cr1 = cross(a, b);
P3 cr2 = cross(b, c);
if (norm(cr1) != norm(cr2))
cost++;
}
}
dap = min(dap, cost);
}
for (int j = 0; j < 3; j++)
arg[j] = -arg[j];
}
return 1000 + dap;
}
int main() {
int n;
cin >> n;
if (n == 1) {
cout << "-1\n";
return 0;
}
vector<P3> p(n), d(n);
for (int i = 0; i < n; i++) {
for (int j = 0; j < 3; j++)
cin >> p[i][j];
for (int j = 0; j < 3; j++)
cin >> d[i][j];
}
if (is_collinear(p)) {
cout << haveSex(p, d, n) << "\n";
return 0;
}
vector<vector<int>> mtrx(n, vector<int>(n, 1e6));
for (int i = 0; i < n; i++) {
pi ans{lint(1e18), -1};
vector<int> ord;
for (int j = 0; j < n; j++) {
if (i == j)
continue;
ord.push_back(j);
if (norm(p[j] - p[i]) == norm(d[i])) {
ans = min(ans, pi{dist(p[i], p[j]), j});
}
}
sort(all(ord), [&](const int &x, const int &y) { return dist(p[i], p[x]) < dist(p[i], p[y]); });
if (ans[0] < 1e15) {
mtrx[i][ans[1]] = 0;
}
set<P3> s;
for (int j = 0; j < sz(ord); j++) {
auto nrm = norm(p[ord[j]] - p[i]);
if (s.count(nrm))
continue;
s.insert(nrm);
mtrx[i][ord[j]] = min(1, mtrx[i][ord[j]]);
}
}
int ans = hung(mtrx);
assert(ans <= 555);
cout << ans << "\n";
}
Details
Tip: Click on the bar to expand more detailed information
Test #1:
score: 100
Accepted
time: 1ms
memory: 3484kb
input:
7 0 0 0 1 0 0 1 0 0 -1 0 0 2 0 0 1 0 0 3 0 0 1 0 0 4 0 0 1 0 0 5 0 0 1 0 0 6 0 0 -1 0 0
output:
1002
result:
ok single line: '1002'
Test #2:
score: 0
Accepted
time: 1ms
memory: 3512kb
input:
4 66 45 10 73 39 36 95 14 26 47 84 59 14 66 89 89 36 78 16 27 94 79 24 24
output:
4
result:
ok single line: '4'
Test #3:
score: 0
Accepted
time: 1ms
memory: 3420kb
input:
3 0 0 0 1 0 0 1 1 1 1 0 0 2 2 2 1 0 0
output:
1002
result:
ok single line: '1002'
Test #4:
score: 0
Accepted
time: 1ms
memory: 3488kb
input:
3 0 0 0 1 1 1 1 1 1 1 0 0 2 2 2 1 0 0
output:
1001
result:
ok single line: '1001'
Test #5:
score: 0
Accepted
time: 1ms
memory: 3468kb
input:
3 0 0 0 1 0 0 1 1 1 1 0 0 2 2 2 -1 -1 -1
output:
1001
result:
ok single line: '1001'
Test #6:
score: 0
Accepted
time: 0ms
memory: 3468kb
input:
3 0 0 0 1 0 0 1 1 1 1 2 2 2 2 2 -1 -1 -1
output:
1000
result:
ok single line: '1000'
Test #7:
score: 0
Accepted
time: 1ms
memory: 3468kb
input:
3 0 0 0 1 0 0 1 1 1 1 2 2 2 2 2 1 1 1
output:
1001
result:
ok single line: '1001'
Test #8:
score: 0
Accepted
time: 1ms
memory: 3428kb
input:
1 0 0 0 3 1 4
output:
-1
result:
ok single line: '-1'
Test #9:
score: 0
Accepted
time: 1ms
memory: 3540kb
input:
4 0 0 0 1 1 1 1 0 0 -1 0 0 1 1 1 0 -1 0 1 0 1 0 1 0
output:
1
result:
ok single line: '1'
Test #10:
score: -100
Wrong Answer
time: 14ms
memory: 3528kb
input:
500 0 0 0 1 0 0 1 0 0 1 0 0 2 0 0 -1 0 0 3 0 0 1 0 0 4 0 0 1 0 0 5 0 0 1 0 0 6 0 0 1 0 0 7 0 0 1 0 0 8 0 0 1 0 0 9 0 0 1 0 0 10 0 0 -1 0 0 11 0 0 -1 0 0 12 0 0 1 0 0 13 0 0 -1 0 0 14 0 0 1 0 0 15 0 0 1 0 0 16 0 0 1 0 0 17 0 0 -1 0 0 18 0 0 -1 0 0 19 0 0 -1 0 0 20 0 0 -1 0 0 21 0 0 1 0 0 22 0 0 1 0 0...
output:
1242
result:
wrong answer 1st lines differ - expected: '250', found: '1242'