import std.stdio, std.conv, std.array, std.string, std.algorithm, std.container, std.range, core.stdc.stdlib, std.math, std.typecons;
T[][] combinations(T)(T[] s, in int m) {   if (!m) return [[]];   if (s.empty) return [];   return s[1 .. $].combinations(m - 1).map!(x => s[0] ~ x).array ~ s[1 .. $].combinations(m); }

void main() {
  auto N = readln.chomp.to!(long);
  auto X = readln.split.to!(long[]).sort();

  ulong solve() {
    ulong candidate = ulong.max;
    foreach(p; X[0]..X[$-1]+1) {
      auto sum = X.map!(x => p - x).map!(x => x*x).reduce!((a, b) => a + b);
      if (candidate > sum) candidate = sum;
    }

    return candidate;
  }

  solve().writeln;
}
