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| #include <bits/stdc++.h>
#define R register
#define ll long long
#define pir std::pair<ll, ll>
#define mp(i, j) std::make_pair(i, j)
#define sum(a, b, mod) (((a) + (b)) % mod)
#define It std::map<ll, std::vector<ll>>::iterator
const ll MaxN = 1e3 + 10;
ll n, x[MaxN], y[MaxN], f[MaxN];
std::unordered_map<ll, ll> trash;
std::map<ll, std::vector<ll>> lx, ly;
std::vector<std::pair<ll, ll>> X, Y, line;
ll Abs(ll x) { return (x < 0) ? (-x) : x; }
ll cmpx(ll a, ll b) { return x[a] < x[b]; }
ll cmpy(ll a, ll b) { return y[a] < y[b]; }
ll getf(ll x)
{
if (x != f[x])
f[x] = getf(f[x]);
return f[x];
}
void merge(ll x, ll y)
{
ll fx = getf(x), fy = getf(y);
if (fx != fy) f[fx] = fy;
}
inline ll read()
{
ll x = 0, f = 1;
char ch = getchar();
while (ch > '9' || ch < '0')
{
if (ch == '-')
f = 0;
ch = getchar();
}
while (ch <= '9' && ch >= '0')
x = (x << 1) + (x << 3) + (ch ^ 48), ch = getchar();
return f ? x : (-x);
}
ll check(ll mid)
{
trash.clear();
for (ll i = 1; i <= n; i++)
f[i] = i;
for (It it = lx.begin(); it != lx.end(); it++)
{
std::vector<ll> &v = it->second;
for (ll i = 1; i < v.size(); i++)
if (Abs(y[v[i]] - y[v[i - 1]]) <= mid)
merge(v[i], v[i - 1]);
}
for (It it = ly.begin(); it != ly.end(); it++)
{
std::vector<ll> &v = it->second;
for (ll i = 1; i < v.size(); i++)
if (Abs(x[v[i]] - x[v[i - 1]]) <= mid)
merge(v[i], v[i - 1]);
}
ll siz = 0;
for (ll i = 1; i <= n; i++)
siz += (trash[getf(i)] == 0), trash[getf(i)] = 1;
if (siz == 1)
return 1;
else if (siz == 2)
{
for (ll i = 1; i <= n; i++)
for (ll j = i + 1; j <= n; j++)
if (f[i] != f[j])
{
if (Abs(x[i] - x[j]) == 0 && Abs(y[i] - y[j]) <= 2 * mid)
return 1;
if (Abs(y[i] - y[j]) == 0 && Abs(x[i] - x[j]) <= 2 * mid)
return 1;
if (Abs(x[i] - x[j]) <= mid && Abs(y[i] - y[j]) <= mid)
return 1;
}
}
else if (siz == 3)
{
line.clear();
for (It it = lx.begin(); it != lx.end(); it++)
{
std::vector<ll> &v = it->second;
for (ll i = 1; i < v.size(); i++)
if (f[v[i]] != f[v[i - 1]])
line.push_back(mp(v[i], v[i - 1]));
}
for (It it = ly.begin(); it != ly.end(); it++)
{
std::vector<ll> &v = it->second;
for (ll i = 1; i < v.size(); i++)
if (f[v[i]] != f[v[i - 1]])
line.push_back(mp(v[i], v[i - 1]));
}
for (auto li : line)
{
ll l = li.first, r = li.second;
for (ll i = 1; i <= n; i++)
{
if (f[l] != f[i] && f[i] != f[r])
{
if (x[l] == x[r])
{
if (Abs(y[l] - y[i]) <= mid && Abs(y[r] - y[i]) <= mid)
if (Abs(x[l] - x[i]) <= mid)
return 1;
}
else if (Abs(x[l] - x[i]) <= mid && Abs(x[r] - x[i]) <= mid)
if (Abs(y[l] - y[i]) <= mid)
return 1;
}
}
}
}
else if (siz == 4)
{
X.clear(), Y.clear();
for (It it = lx.begin(); it != lx.end(); it++)
{
std::vector<ll> &v = it->second;
for (ll i = 1; i < v.size(); i++)
if (f[v[i]] != f[v[i - 1]])
X.push_back(mp(v[i], v[i - 1]));
}
for (It it = ly.begin(); it != ly.end(); it++)
{
std::vector<ll> &v = it->second;
for (ll i = 1; i < v.size(); i++)
if (f[v[i]] != f[v[i - 1]])
Y.push_back(mp(v[i], v[i - 1]));
}
for (auto x1 : X)
{
for (auto y1 : Y)
{
ll a = x1.first, b = x1.second;
ll c = y1.first, d = y1.second;
if (f[a] != f[c] && f[a] != f[d])
if (f[b] != f[c] && f[b] != f[d])
if (Abs(x[a] - x[c]) <= mid && Abs(x[a] - x[d]) <= mid)
if (Abs(y[c] - y[a]) <= mid && Abs(y[c] - y[b]) <= mid)
return 1;
}
}
}
return 0;
}
signed main()
{
n = read();
for (ll i = 1; i <= n; i++)
{
x[i] = read(), y[i] = read();
lx[x[i]].push_back(i);
ly[y[i]].push_back(i);
}
for (It it = lx.begin(); it != lx.end(); it++)
{
std::vector<ll> &v = it->second;
std::sort(v.begin(), v.end(), cmpy);
}
for (It it = ly.begin(); it != ly.end(); it++)
{
std::vector<ll> &v = it->second;
std::sort(v.begin(), v.end(), cmpx);
}
ll l = 1, r = 0x7f7f7f7f;
while (l < r)
{
ll mid = (l + r) >> 1;
if (check(mid))
r = mid;
else
l = mid + 1;
}
if (l == 0x7f7f7f7f)
l = -1;
printf("%lld\n", l);
return 0;
}
|