import sequtils,strutils,algorithm,math,sugar,macros,strformat
template get*():string = stdin.readLine().strip()
template `min=`*(x,y) = x = min(x,y)

let n = get().parseInt()
let X = get().split().map(parseInt).sorted(cmp)
var res = X[^1] - X[0]
for i in 1..<n: res .min= X[i] - X[i-1]
echo res