// 深度优先遍历框架
void dfs(int x) {
v[x] = 1;
for (int i = head[x]; i; i = next[i]) {
int y = ver[i];
if (v[y]) continue;
dfs(y);
}
}
// DFS序
void dfs(int x) {
a[++m] = x;
v[x] = 1;
for (int i = head[x]; i; i = next[i]) {
int y = ver[i];
if (v[y]) continue;
dfs(y);
}
a[++m] = x;
}
// 求树中各点的深度
void dfs(int x) {
v[x] = 1;
for (int i = head[x]; i; i = next[i]) {
int y = ver[i];
if (v[y]) continue; // 点y已经被访问过了
d[y] = d[x] + 1;
dfs(y);
}
}
// 求树的重心
void dfs(int x) {
v[x] = 1; size[x] = 1; // 子树x的大小
int max_part = 0; // 删掉x后分成的最大子树的大小
for (int i = head[x]; i; i = next[i]) {
int y = ver[i];
if (v[y]) continue; // 点y已经被访问过了
dfs(y);
size[x] += size[y];
max_part = max(max_part, size[y]);
}
max_part = max(max_part, n - size[x]);
if (max_part < ans) {
ans = max_part;
pos = x;
}
}
// 划分图的连通块
void dfs(int x) {
v[x] = cnt;
for (int i = head[x]; i; i = next[i]) {
int y = ver[i];
if (v[y]) continue;
dfs(y);
}
}
for (int i = 1; i <= n; i++)
if (!v[i]) {
cnt++;
dfs(i);
}
// 广度优先遍历框架
void bfs() {
memset(d, 0, sizeof(d));
queue<int> q;
q.push(1); d[1] = 1;
while (q.size()) {
int x = q.front(); q.pop();
for (int i = head[x]; i; i = next[i]) {
int y = ver[i];
if (d[y]) continue;
d[y] = d[x] + 1;
q.push(y);
}
}
}
// 拓扑排序
void add(int x, int y) { // 在邻接表中添加一条有向边
ver[++tot] = y, next[tot] = head[x], head[x] = tot;
deg[y]++;
}
void topsort() {
queue<int> q;
for (int i = 1; i <= n; i++)
if (deg[i] == 0) q.push(i);
while (q.size()) {
int x = q.front(); q.pop();
a[++cnt] = x;
for (int i = head[x]; i; i = next[i]) {
int y = ver[i];
if (--deg[y] == 0) q.push(y);
}
}
}
int main() {
cin >> n >> m; // 点数、边数
for (int i = 1; i <= m; i++) {
int x, y;
scanf("%d%d", &x, &y);
add(x, y);
}
topsort();
for (int i = 1; i <= cnt; i++)
printf("%d ", a[i]);
cout << endl;
}