// URL: https://yukicoder.me/problems/no/168 import std.algorithm, std.array, std.bitmanip, std.container, std.conv, std.format, std.functional, std.math, std.range, std.traits, std.typecons, std.stdio, std.string; version(unittest) {} else void main() { int N; io.getV(N); Point[] p; io.getS!("x", "y")(N, p); struct D { int s, t; long d; } D[] d; foreach (i; 0..N) foreach (j; i+1..N) d ~= D(i, j, (p[i]-p[j]).hypot2); d.sort!"a.d di.d <= l^^2)(false).front); return; } } } pure nothrow @nogc @safe { auto lowerBoundBy(alias conv = "a", alias comp = "a tuple(e, convFun(e))).assumeSorted!((a, b) => compFun(a[1], b[1])); } } alias Point = Point2!long; struct Point2(T) { T x, y; pure nothrow @nogc @safe { Point2!T opBinary(string op)(const Point2!T r) const if (op == "+" || op == "-") { return mixin("Point2(x"~op~"r.x, y"~op~"r.y)"); } Point2!T opOpAssign(string op)(const Point2!T r) if (op == "+" || op == "-") { mixin("x"~op~"=r.x; y"~op~"=r.y;"); return this; } Point2!T opBinary(string op, U)(U a) const if ((op == "*" || op == "/") && isIntegral!U) { return mixin("Point2(x"~op~"a, y"~op~"a)"); } Point2!T opOpAssign(string op, U)(U a) if ((op == "*" || op == "/") && isIntegral!U) { mixin("x"~op~"=a; y"~op~"=a;"); return this; } T opBinary(string op: "*")(const Point2!T r) const { return x*r.x+y*r.y; } T hypot2() const { return x^^2+y^^2; } } } pure nothrow @nogc @safe { T distManhattan(T)(const Point2!T p1, const Point2!T p2) { return (p1.x-p2.x).abs + (p1.y-p2.y).abs; } T cross(T)(const Point2!T p1, const Point2!T p2) { return p1.x*p2.y - p1.y*p2.x; } } struct Point3(T) { T x, y, z; pure nothrow @nogc @safe { Point3!T opBinary(string op)(const Point3!T r) const if (op == "+" || op == "-") { return mixin("Point3!T(x"~op~"r.x, y"~op~"r.y, z"~op~"r.z)"); } Point3!T opOpAssign(string op)(const Point3!T r) if (op == "+" || op == "-") { mixin("x"~op~"=r.x; y"~op~"=r.y; z"~op~"=r.z;"); return this; } Point3!T opBinary(string op, U)(U a) const if ((op == "*" || op == "/") && isIntegral!U) { return mixin("Point3!T(x"~op~"a, y"~op~"a, z"~op~"a)"); } Point3!T opOpAssign(string op, U)(U a) if ((op == "*" || op == "/") && isIntegral!U) { mixin("x"~op~"=a; y"~op~"=a; z"~op~"=a;"); return this; } T opBinary(string o: "*")(const Point3!T r) const { return x*r.x+y*r.y+z*r.z; } T hypot2() const { return x^^2+y^^2+z^^2; } } } pure nothrow @nogc @safe { Point3!T cross(T)(const Point3!T p1, const Point3!T p2) { return Point3!T(p1.y*p2.z - p1.z*p2.y, p1.z*p2.x - p1.x*p2.z, p1.x*p2.y - p1.y*p2.x); } } class UnionFind { int n; pure nothrow @safe { this(int n) { this.n = this.s = n; p = new int[](n); p[] = s; cf = n; cn = new size_t[](n); cn[] = 1; } } pure nothrow @nogc @safe { bool unite(int u, int v) in { assert(0 <= u && u < n && 0 <= v && v < n); } do { auto pu = subst(u), pv = subst(v); if (pu != pv) { p[pv] = pu; --cf; cn[pu] += cn[pv]; return true; } else { return false; } } bool isSame(int u, int v) in { assert(0 <= u && u < n && 0 <= v && v < n); } do { return subst(u) == subst(v); } size_t countForests() { return cf; } size_t countNodes(int u) { return cn[subst(u)]; } } pure nothrow @safe { auto groups() { auto g = new int[][](n); foreach (i; 0..n) g[subst(i)] ~= i; return g.filter!(l => !l.empty); } } private { int[] p; int s; size_t cf; size_t[] cn; pure nothrow @nogc @safe { int subst(int i) { return p[i] == s ? i : (p[i] = subst(p[i])); } } } } pure nothrow @safe { auto unionFind(int n) { return new UnionFind(n); } } auto io = IO!()(); import std.stdio; struct IO(alias IN = stdin, alias OUT = stdout) { import std.meta : allSatisfy; import core.stdc.stdlib : exit; void getV(T...)(ref T v) { foreach (ref w; v) get(w); } void getA(T)(size_t n, ref T v) if (hasAssignableElements!T) { v = new T(n); foreach (ref w; v) get(w); } void getC(T...)(size_t n, ref T v) if (allSatisfy!(hasAssignableElements, T)) { foreach (ref w; v) w = new typeof(w)(n); foreach (i; 0..n) foreach (ref w; v) get(w[i]); } void getM(T)(size_t r, size_t c, ref T v) if (hasAssignableElements!T && hasAssignableElements!(ElementType!T)) { v = new T(r); foreach (ref w; v) getA(c, w); } template getS(E...) { void getS(T)(size_t n, ref T v) { v = new T(n); foreach (ref w; v) foreach (e; E) mixin("get(w."~e~");"); } } const struct PutConf { bool newline = true, flush, exit; string floatFormat = "%.10f", delimiter = " "; } void put(alias conf = "{}", T...)(T v) { mixin("const PutConf c = "~conf~"; putMain!c(v);"); } void putB(alias conf = "{}", S, T)(bool c, S t, T f) { if (c) put!conf(t); else put!conf(f); } void putRaw(T...)(T v) { OUT.write(v); OUT.writeln; } private { dchar[] buf; auto sp = (new dchar[](0)).splitter; void nextLine() { IN.readln(buf); sp = buf.splitter; } void get(T)(ref T v) { if (sp.empty) nextLine(); v = sp.front.to!T; sp.popFront(); } void putMain(PutConf c, T...)(T v) { foreach (i, w; v) { putOne!c(w); if (i+1 < v.length) OUT.write(c.delimiter); } static if (c.newline) OUT.writeln; static if (c.flush) OUT.flush(); static if (c.exit) exit(0); } void putOne(PutConf c, T)(T v) { static if (isInputRange!T && !isSomeString!T) putRange!c(v); else static if (isFloatingPoint!T) OUT.write(format(c.floatFormat, v)); else static if (hasMember!(T, "fprint")) v.fprint(OUT); else OUT.write(v); } void putRange(PutConf c, T)(T v) { auto w = v; while (!w.empty) { putOne!c(w.front); w.popFront(); if (!w.empty) OUT.write(c.delimiter); } } } }