if let input1 = readLine(),
   let NM = input1.split(separator: " ").compactMap({Int($0)}) as? [Int],
   let N = NM.first, let M = NM.last
{
    var graph: [[Int]] = Array(repeating: [], count: N+1)
    var inDegree = Array(repeating: 0, count: N+1)
    
    for _ in 1...M {
        guard let input2 = readLine(),
              let uv = input2.split(separator: " ").compactMap({Int($0)}) as? [Int],
              let u = uv.first, let v = uv.last
        else { break }
        
        graph[u].append(v)
        inDegree[v] += 1
    }
    
    var qu: [Int] = []
    var idx = 0
    
    for n in 1...N {
        if inDegree[n] == 0 { qu.append(n) }
    }
    
    while idx < qu.count {
        let num = qu[idx]
        idx += 1
        
        for nxt in graph[num] {
            inDegree[nxt] -= 1
            if inDegree[nxt] == 0 { qu.append(nxt) }
        }
    }
    
    print(qu.map{ String($0) }.joined(separator: " "))
}