#include 
     
      using namespace std;const int maxn = 5e5 + 10;int N, M;int h[maxn], v[maxn], in[maxn], nx[maxn];int  sz = 0;void init() {    for(int i = 1; i <= N; i ++) {        h[i] = -1;        in[i] = 0;    }    sz = 0;}void add(int a, int b) {    v[sz] = b;    nx[sz] = h[a];    h[a] = sz;    in[b] ++;    sz ++;}void TopSort() {    queue
      
        q;    vector
       
         ans;    for(int i = 1; i <= N; i ++) {        if(in[i] == 0)            q.push(i);    }    while(!q.empty()) {        int tp = q.front();        q.pop();        ans.push_back(tp);        for(int i = h[tp]; i != -1; i = nx[i]) {            in[v[i]] --;            if(in[v[i]] == 0)                q.push(v[i]);        }    }    if(ans.size() != N)        printf("NO\n");    else {        for(int i = 0; i < ans.size(); i ++)            printf("%d%s", ans[i], i != ans.size() - 1 ? " " : "\n");    }}int main() {    while(~scanf("%d%d", &N, &M)) {        init();        for(int i = 0; i < M; i ++) {            int a, b;            scanf("%d%d", &a, &b);            add(a, b);        }        TopSort();    }    return 0;}
       
      
     

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