//: Playground - noun: a place where people can play

func makeReadLineMethod()->()->String? {
    var initStr:[String] = [
        "4",
        "0 1 1 0"
    ]
    var idx = -1;
    func proc()->String? {
        idx+=1
        return initStr[idx];
    }
    return proc;
}
var readLine = makeReadLineMethod();


let pointCount = Int(readLine()!);

let points = readLine()!.split(separator: " ").map({Int($0)!}).sorted(by: {$0<$1});

var ans = abs(points.first!-points.last!);

for i in 1...points.count-1 {
    let tmp = points[i]-points[i-1];
    if(tmp>0) {
        ans=min(ans, tmp);
    }
}
print(ans);