import std.stdio, std.string, std.conv, std.algorithm;
import std.range, std.array, std.container, std.math, std.typecons;

immutable int mod = 10^^9 + 7;

int N;
int[] x;

void main() {
    N = readln.chomp.to!int;
    x = readln.split.to!(int[]).sort().uniq.array;
    N = x.length.to!int;

    if (x.length == 1) writeln(0);
    else iota(N - 1).map!(i => x[i + 1] - x[i]).minElement.writeln;
}