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);