# | Time | Username | Problem | Language | Result | Execution time | Memory |
---|---|---|---|---|---|---|---|
434692 | frodakcin | Comparing Plants (IOI20_plants) | C++11 | 0 ms | 0 KiB |
This submission is migrated from previous version of oj.uz, which used different machine for grading. This submission may have different result if resubmitted.
#include "plants.h"
#include <queue>
#include <bitset>
namespace SLOW_SOLN
{
const int MN = 5e3+10;
const int INF = 0x3f3f3f3f;
int N, K, ts[MN], ctr;
bool v[MN];
std::vector<int> a[MN]; // i > a[i][...] -- dag
std::bitset<MN> vis[MN];
void dfs(int n)
{
v[n]=1;
for(int x:a[n])
if(!v[x])
dfs(x);
ts[ctr++]=n;
}
void init(int k, std::vector<int> r) {
K=k, N=r.size();
std::queue<int> q;
int zc=0;
for(int i=N-K;i<N;++i)
zc += !r[i];
for(int i=0;i<N;++i)
{
zc -= !r[(N-K+i)%N];
if(zc==0 && r[i]==0)
q.push(i);
zc += !r[i];
}
for(;!q.empty();)
{
int n=q.front(); q.pop();
if(r[n] < 0) continue;
// check
bool ok=1;
for(int i=1;i<K;++i)
if(r[(n-i+N)%N]==0)
ok=0;
if(!ok) continue;
// add
r[n]=-1;
for(int i=K-1;i>0;--i)
--r[(n-i+N)%N];
for(int i=1;i<K;++i)
if(r[(n+i)%N] == 0)
{
q.push((n+i)%N);
break;
}
for(int i=K-1;i>0;--i)
if(r[(n-i+N)%N] == 0)
{
q.push((n-i+N)%N);
break;
}
for(int i=1;i<K;++i)
if(r[(n+i)%N] >= 0)
a[n].push_back((n+i)%N);
for(int i=1;i<K;++i)
if(r[(n-i+N)%N] >= 0)
a[n].push_back((n-i+N)%N);
}
for(int i=0;i<N;++i)
if(!v[i])
dfs(i);
for(int i=0;i<N;++i)
vis[i].set(i);
for(int i=0;i<N;++i)
for(int x:a[ts[i]])
vis[ts[i]]|=vis[x];
return;
}
int compare_plants(int x, int y)
{
if(vis[x][y]) return 1;
if(vis[y][x]) return -1;
return 0;
}
}
template<typename T> bool ckmin(T& a, const T& b) {return b<a?a=b,1:0;}
template<typename T> bool ckmax(T& a, const T& b) {return b>a?a=b,1:0;}
const int MN = 2e5+10;
const int INF = 0x3f3f3f3f;
int N, K, ts[MN], ctr, ord[MN];
bool v[MN], done[MN];
//Minmax Segtree
struct minmax
{
public:
int min, max;
minmax(int _mn=INF, int _mx=-INF): min(_mn), max(_mx) {}
minmax& operator += (const int& o) {min += o, max += o; return *this;}
minmax& operator -= (const int& o) {min -= o, max -= o; return *this;}
minmax& operator += (const minmax& o) {ckmin(min, o.min); ckmax(max, o.max); return *this;}
friend minmax operator + (minmax a, const int& b) {return a+=b;}
friend minmax operator - (minmax a, const int& b) {return a-=b;}
friend minmax operator + (minmax a, const minmax& b) {return a+=b;}
bool contains(int x) {return min <= x && x <= max;}
bool contains(const minmax& x) {return min <= x.min && x.max <= max;}
} range[MN];
minmax mv[1 << 19];
minmax mqry(int n, int l, int r, int ql, int qr)
{
if(ql <= l && r <= qr) return mv[n];
else
{
int m=l+(r-l)/2; minmax f;
if(ql < m) f += mqry(n<<1, l, m, ql, qr);
if(m < qr) f += mqry(n<<1|1, m, r, ql, qr);
return f;
}
}
void mupd(int n, int l, int r, int q, minmax val)
{
if(r-l>1)
{
int m=l+(r-l)/2;
if(q < m) mupd(n<<1, l, m, q, val);
else mupd(n<<1|1, m, r, q, val);
mv[n]=mv[n<<1]+mv[n<<1|1];
}
else
mv[n]=val;
}
//R segment tree
int rv[1 << 19], rz[1 << 19];
void rupd(int n, int x) {rv[n] += x, rz[n] += x;}
void rdown(int n)
{
if(rz[n])
{
rupd(n<<1, rz[n]);
rupd(n<<1|1, rz[n]);
rz[n]=0;
}
}
void rupd(int n, int l, int r, int ql, int qr, int x)
{
if(ql <= l&&r <= qr) rupd(n, x);
else
{
int m=l+(r-l)/2;
rdown(n);
if(ql < m) rupd(n<<1, l, m, ql, qr, x);
if(m < qr) rupd(n<<1|1, m, r, ql, qr, x);
rv[n] = std::min(rv[n<<1], rv[n<<1|1]);
}
}
int rqry(int n, int l, int r, int ql) // return leftmost zero
{
if(rv[n] > 0) return r;
else if(r-l>1)
{
int m=l+(r-l)/2, f=m;
rdown(n);
if(ql < m) f=rqry(n<<1, l, m, ql);
if(f == m) f=rqry(n<<1|1, m, r, ql);
return f;
}
else return l;
}
void init(int k, std::vector<int> r) {
K=k, N=r.size();
if(N <= 5000)
{
return slow_soln::init(k, r);
}
std::queue<int> q;
int zc=0;
for(int i=N-K;i<N;++i)
zc += !r[i];
for(int i=0;i<N;++i)
{
zc -= !r[(N-K+i)%N];
if(zc==0 && r[i]==0)
q.push(i);
zc += !r[i];
}
for(int i=0;i<N;++i)
rupd(1, 0, N, i, i+1, r[i]);
for(;!q.empty();)
{
int n=q.front(); q.pop();
if(done[n]) continue;
// check
int loc = rqry(1, 0, N, n-K+1);
//printf("?? %d (%d)\n", n, loc);
if(loc < n) continue;
if(n-K+1 < 0 && rqry(1, 0, N, n-K+1+N) < N) continue;
// add
rupd(1, 0, N, n, n+1, INF);
//printf("TEST [%d] %d\n", n, rqry(1, 0, N, 0));
rupd(1, 0, N, n-K+1, n, -1);
if(n-K+1 < 0) rupd(1, 0, N, n-K+1+N, N, -1);
loc = rqry(1, 0, N, n);
if(loc < std::min(N, n+K))
q.push(loc);
else if(n+K>N)
{
loc = rqry(1, 0, N, 0);
if(loc<n+K-N)
q.push(loc);
}
loc = N;
if(n-K+1 < 0)
loc = rqry(1, 0, N, n-K+1+N);
if(loc < N)
q.push(loc);
else
{
loc = rqry(1, 0, N, n-K+1);
if(loc < n)
q.push(loc);
}
//modify ans
ts[ctr]=n;
ord[n]=ctr++;
done[n]=1;
}
for(int i=N-1, n;i>=0;--i)
{
n=ts[i];
range[n] = minmax(n, n);
range[n] += mqry(1, 0, N, n-K+1, n+K);
if(n+K>N) range[n] += mqry(1, 0, N, 0, n+K-N)+N;
if(n-K+1<0) range[n] += mqry(1, 0, N, n-K+1+N, N)-N;
mupd(1, 0, N, n, range[n]);
//printf("%d: %d <-> %d\n", n, range[n].min, range[n].max);
}
return;
}
bool cover(int a, int b) // is a > b?
{
if(ord[a]>ord[b]) return 0;
return range[a].contains(range[b]) || range[a].contains(range[b]+N) || range[a].contains(range[b]-N);
}
int compare_plants(int x, int y)
{
if(N <= 5000)
{
return slow_soln::compare_plants(x, y);
}
if(cover(x, y)) return 1;
if(cover(y, x)) return -1;
return 0;
}