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authorGloria Mundi <gloria@gloria-mundi.eu>2024-11-16 01:24:14 +0100
committerGloria Mundi <gloria@gloria-mundi.eu>2024-11-16 01:24:14 +0100
commit98567ec798aa8ca2cfbcb85c774dd470f30e30d4 (patch)
tree5113d5cc24d1ad5f93810b6442ce584a36950dc8 /content/geometry/closestPair.cpp
parentad3856a6b766087df0036de0b556f4700a6498c9 (diff)
parent8d11c6c8213f46f0fa19826917c255edd5d43cb1 (diff)
mzuenni tests
Diffstat (limited to 'content/geometry/closestPair.cpp')
-rw-r--r--content/geometry/closestPair.cpp27
1 files changed, 27 insertions, 0 deletions
diff --git a/content/geometry/closestPair.cpp b/content/geometry/closestPair.cpp
new file mode 100644
index 0000000..9b115f3
--- /dev/null
+++ b/content/geometry/closestPair.cpp
@@ -0,0 +1,27 @@
+ll rec(vector<pt>::iterator a, int l, int r) {
+ if (r - l < 2) return INF;
+ int m = (l + r) / 2;
+ ll midx = a[m].real();
+ ll ans = min(rec(a, l, m), rec(a, m, r));
+
+ inplace_merge(a+l, a+m, a+r, [](const pt& x, const pt& y) {
+ return x.imag() < y.imag();
+ });
+
+ pt tmp[8];
+ fill(all(tmp), a[l]);
+ for (int i = l + 1, next = 0; i < r; i++) {
+ if (ll x = a[i].real() - midx; x * x < ans) {
+ for (pt& p : tmp) ans = min(ans, norm(p - a[i]));
+ tmp[next++ & 7] = a[i];
+ }
+ }
+ return ans;
+}
+
+ll shortestDist(vector<pt> a) { // sz(pts) > 1
+ sort(all(a), [](const pt& x, const pt& y) {
+ return x.real() < y.real();
+ });
+ return rec(a.begin(), 0, sz(a));
+}