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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 |
---|---|---|---|---|---|---|---|---|---|
#128405 | #6570. Who Watches the Watchmen? | installb# | WA | 1ms | 9800kb | C++14 | 4.9kb | 2023-07-20 22:35:53 | 2023-07-20 22:35:56 |
Judging History
answer
#include <bits/stdc++.h>
using namespace std;
typedef long long ll;
const int N = 2005;
const int M = 1000005;
struct point{
int x,y,z; int id;
point (int _x = 0,int _y = 0,int _z = 0) : x(_x), y(_y), z(_z) {}
}p[N],d[N],sp[N];
bool cmp(point p1,point p2){
if(p1.x != p2.x) return p1.x < p2.x;
if(p1.y != p2.y) return p1.y < p2.y;
return p1.z < p2.z;
}
point simpl(const point &p){
int x = abs(__gcd(p.x,__gcd(p.y,p.z)));
return point(p.x / x,p.y / x,p.z / x);
}
point operator - (const point &p1,const point &p2){
return point(p1.x - p2.x,p1.y - p2.y,p1.z - p2.z);
}
point operator + (const point &p1,const point &p2){
return point(p1.x + p2.x,p1.y + p2.y,p1.z + p2.z);
}
point det(const point &p1,const point &p2){
return point(p1.y * p2.z - p1.z * p2.y,p1.z * p2.x - p1.x * p2.z,p1.x * p2.y - p1.y * p2.x);
}
ll dot(const point &p1,const point &p2){
return 1ll * p1.x * p2.x + 1ll * p1.y * p2.y + 1ll * p1.z * p2.z;
}
int len(const point &p){
return abs(p.x) + abs(p.y) + abs(p.z);
}
bool operator == (const point &p1,const point &p2){
return p1.x == p2.x && p1.y == p2.y && p1.z == p2.z;
}
bool operator != (const point &p1,const point &p2){
return p1.x != p2.x || p1.y != p2.y || p1.z != p2.z;
}
bool eq(const point &p1,const point &p2){
return simpl(p1) == simpl(p2) || simpl(p1) == point(0,0,0) - simpl(p2);
}
void input(point &p){
cin >> p.x >> p.y >> p.z;
}
int ec = 1,to[M << 1],nxt[M << 1],cap[M << 1],w[M << 1];
int hed[N];
void add_edge(int f,int t,int c,int d){
++ ec; to[ec] = t; nxt[ec] = hed[f]; hed[f] = ec; cap[ec] = c; w[ec] = d;
++ ec; to[ec] = f; nxt[ec] = hed[t]; hed[t] = ec; cap[ec] = 0; w[ec] = -d;
}
int dis[N],inq[N],flw[N],pre[N],prv[N];
const int INF = 0x3f3f3f3f;
int spfa(int s,int t){
for(int i = 1;i <= t;i ++){
dis[i] = INF; inq[i] = 0; flw[i] = 0;
}
prv[t] = -1;
queue <int> q;
q.push(s); inq[s] = 1; dis[s] = 0; flw[s] = INF;
while(!q.empty()){
int u = q.front(); q.pop();
inq[u] = 0;
for(int i = hed[u];i;i = nxt[i]){
int v = to[i];
if(dis[v] > dis[u] + w[i] && cap[i]){
dis[v] = dis[u] + w[i];
prv[v] = u;
pre[v] = i;
flw[v] = min(flw[u],cap[i]);
if(!inq[v]){
q.push(v);
inq[v] = 1;
}
}
}
}
return prv[t] != -1;
}
int mcf = 0,mxf = 0;
void mcmf(int s,int t){
while(spfa(s,t)){
mxf += flw[t];
mcf += flw[t] * dis[t];
int now = t;
while(now != s){
cap[pre[now]] -= flw[t];
cap[pre[now] ^ 1] += flw[t];
now = prv[now];
}
}
}
int n;
void solve(){
cin >> n;
for(int i = 1;i <= n;i ++){
input(p[i]);
input(d[i]);
p[i].id = i;
}
int S = n + n + 1;
int T = S + 1;
for(int i = 1;i <= n;i ++){
point di = simpl(d[i]);
for(int j = 1;j <= n;j ++) if(j != i) sp[j] = simpl(p[j] - p[i]);
for(int j = 1;j <= n;j ++){
if(i == j) continue;
if(sp[j] == di){
int fl = 0;
for(int k = 1;k <= n;k ++){
if(k == i || k == j) continue;
if(sp[k] == di && len(p[k] - p[i]) < len(p[j] - p[i])){
fl = 1; break;
}
}
if(!fl) add_edge(i,j + n,1,0);
}
else add_edge(i,j + n,1,1);
}
add_edge(S,i,1,0);
add_edge(i + n,T,1,0);
}
mcmf(S,T);
if(mxf == n){
cout << mcf << '\n';
return;
}
int del = 0;
for(int id = 1;id <= n;id ++){
vector <point> G;
for(int i = 1;i <= n;i ++){
if(i == id) continue;
G.push_back(p[i]);
}
sort(G.begin(),G.end(),cmp);
point b = G[0];
point e = G.back();
// id -> b -> e
int cur = 0;
if(dot(det(e - b,d[id]),d[e.id]) == 0 && !eq(d[e.id],e - b) && !eq(d[id],e - b)) cur = 2;
if(!eq(d[e.id],e - b) || !eq(d[id],e - b)) cur = 1;
for(int i = 0;i + 1 < G.size();i ++){
if(simpl(d[G[i].id]) == simpl(G[i + 1].id - G[i].id)) cur ++;
}
del = max(del,cur);
// id -> e -> b
cur = 0;
if(dot(det(e - b,d[id]),d[e.id]) == 0 && !eq(d[e.id],e - b) && !eq(d[id],e - b)) cur = 2;
if(!eq(d[e.id],e - b) || !eq(d[id],e - b)) cur = 1;
for(int i = G.size() - 1;i >= 1;i --){
if(simpl(d[G[i].id]) == simpl(G[i - 1].id - G[i].id)) cur ++;
}
del = max(del,cur);
}
cout << 1000 + n - del << '\n';
}
int main(){
ios::sync_with_stdio(false);
solve();
return 0;
}
详细
Test #1:
score: 0
Wrong Answer
time: 1ms
memory: 9800kb
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:
1
result:
wrong answer 1st lines differ - expected: '1002', found: '1'