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/*
  Copyright 2011 Marek "p2004a" Rusinowski
  Tarjan algorithm
*/
#include <cstdio>
#include <vector>
 
#define MAXN 1000000
 
std::vector<int> edges[MAXN];
bool visited[MAXN];
std::vector<int> sorted;
 
void dfs(int v) {
  visited[v] = true;
  for (unsigned i = 0; i < edges[v].size(); ++i) {
    if (!visited[edges[v][i]]) {
      dfs(edges[v][i]);
    }
  }
  sorted.push_back(v);
}
 
int main() {
  int a, b, n, m;
  scanf("%d %d", &n, &m);
  for (int i = 0; i < m; ++i) {
    scanf("%d %d", &a, &b);
    edges[--a].push_back(--b);
  }
  for (int i = 0; i < n; ++i) {
    if (!visited[i]) {
      dfs(i);
    }
  }
  for (int i = n - 1; i >= 0; --i) {
    printf("%d ", sorted[i] + 1);
  }
  printf("\n");
  return 0;
}
 

prog.cpp: In function ‘int main()’:
prog.cpp:26: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result
prog.cpp:28: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result

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